L. and Energy Devices

Organizers: Zhiyong Fan, Guozhen Shen, Jiatao Zhang, Yu-Lun Chueh, Hyunhyub Ko, Sang-Woo Kim, Kuniharu Takei, Hong-Ming Lin

L-01 Three-dimensional Metal Halide Perovskite Nanowire Arrays and Optoelectronic Devices Zhiyong Fan, Leilei Gu, Mohammad Tavakoli, Aashir Waleed The Hong Kong University of Science and

Metal halide perovskite materials are emerging as highly promising materials for high performance optoelectronic devices thus triggered broad attention globally. In this work, we report for the first time a chemical vapor deposition (CVD) process to grow ordered three-dimensional (3-D) metal halide nanowire (NW) arrays in nanoengineering templates. This unique CVD process utilizes metal nanoclusters at the bottom of vertical nanochannels to initiate high quality NW growth. As the nanochannels have largely controllable geometrical factors, namely, periodicity, diameter and depth, NW geometry can also be precisely nanoengineered. As the result, the ordered 3-D NW arrays can achieve ultra-high NW density in the range of 4×108/cm2~109/cm2 at a sizable scale of ~9 cm2. The 3-D NW arrays are conspicuously promising for 3-D integrated nano-electronics/optoelectronics. To further demonstrate the technological potency of the perovskite NW arrays, they have been fabricated into proof-of-concept image sensors. Each image sensor consists of 1,024 photodiode pixels made of vertical perovskite NWs, and the imaging functionality has been verified by recognizing various optical patterns projected on the sensor. In addition, we have also discovered that the chemically and mechanically robust template can effectively protect perovskite NWs from water and oxygen invasion thus the material stability is significantly better than planar perovskite films confirmed by photoluminescence and photoelectric measurements.

L-02 Evolution of filament formation in RRAM devices Xing Wu Department of Electrical , East China Normal University, 500 Dongchuan Road, Shanghai 200241, China

Objectives: Real-time high-resolution, electrical, chemical, and morphological TEM characterization was carried out on planar FIB-patterned Ni gated dual oxide layers RRAM devices to study the structural and compositional evolution of multiple nanofilaments (MNFs) in the dielectric stack [1]. Methods and Results: We use in-situ TEM to electrically turn on and off the RRAM devices. The formation of single and multiple MNFs were observed, and our results point to the possibility of large variations in the size of different MNFs in the case of multiple filaments formation, as the amount of migrating Ni can greatly vary, leading to different patterns and sizes of MNFs. The MNFs are confirmed to be shaped as “truncated cones,” with the broader side closer to the anode end (i.e., Ni electrode). Furthermore, we observe Ni depletion in the Ni electrode adjacent to the location of the filaments in SET conditions, as well as residual Ni fragments in the dielectric stack after RESET. The unique set of the experimental characterization methods applied in this work and the detailed analysis presented supplies a route to the in-depth characterization of nanoscale filamentation. Conclusions: The presented results directly provide critical information for optimizing the design of future RRAM

1 devices with improved performance and reliability (i.e., narrowing of switching window) and with reduced material/operational variance in both the HRS and LRS. Our following work will involve the TEM-based analysis of the spatial correlation of multiple filaments as well as the size dependence of these nucleated filaments on the compliance setting used for forming and SET events, and future low-power spintronics devices. The experimental routines presented here are broadly applicable for the high-resolution characterization of 2D devices [2-6], and will lead to new physical insight in a range of 2D layered materials-based polar devices. References: 1. Advanced Electronic Materials 1, 11, (2015). 2. Nano Lett., 16(4), 2548, (2016). 3. Science Advances, 1:e1500462, (2015). 4. Science, 344(6184), 616, (2014). 5. Nat. Comm. 5, 3688, (2014). 6. Nat. Comm. 4, 1776, (2013). Keywords: in-situ TEM; RRAM; dynamic characterization

L-03 Hierarchical NiMo-Based 3D Electrocatalysts for Highly-Efficient Hydrogen Evolution in Alkaline Conditions Johnny C. Ho City University of Hong Kong

In recent years, electro- or photoelectrochemical water splitting represents a promising route for renewable hydrogen generations but still requires the substantial development of efficient and cost-effective catalysts to further reduce the energy losses and material costs for scalable and practical applications. Here, we report the design and development of a hierarchical electrocatalyst constructed from microporous nickel foam and well-assembled bimetallic nickel-molybdenum (NiMo) nanowires, which are capable to deliver current densities as comparable to those of the state-of-the-art Pt/C catalyst at low overpotentials and even larger current densities at higher overpotentials (> 124 mV). This binder-free 3D hydrogen evolution cathode catalyst also exhibits the excellent stability, without any decay of the current density observed after long-term stability tests at a low current density of 10 mA cm-2 and a high current density of 50 mA cm-2. By pairing this NiMo 3D cathode with a NiFe-based anode, a water electrolyzer can be achieved with a stable current density of 10 mA cm-2 for overall water splitting at a voltage of ~1.53 V, indicating that the water splitting can be indeed realized without any performance sacrifice by using earth abundant electrocatalysts. Keywords: electrocatalysis, nickel-molybdenum alloys, hierarchical nanostrutures, hydrogen evolution

L-04 Plasmonic with hidden helicity and optical activity Zhifeng Huang Hong Kong Baptist University

The geometrical prerequisite for forming a helix is P (helical pitch) > d (wire diameter). Limited by the current development of nano-fabrication techniques, it is difficult to minimize d and consequently P to the sub-10-nm molecule-comparable scale, preventing the study of chiral plasmonics at dimensions approaching the physical limit. Herein, we operate glancing angle deposition at substrate temperature of 0 °C and high speed of substrate

2 rotation to generate silver nanoparticles (AgNPs) with nominal P < d. The AgNPs have intrinsic chiroptical activity characterized by circular dichroism (CD), originating from the hidden helicity. With increasing P from 3 to 66 nm, the plasmonic mode barely shifts but shows a logarithmic increase in CD amplitude. Immersing AgNPs in water causes the plasmonic mode to redshift and rise in CD amplitude, i.e., a water effect on chiroptical activity. Hydrophilic AgNP arrays with low array porosity show a reversible water effect, but hydrophobic Ag nanospiral arrays with P > d and high array porosity have an irreversible water effect. This work introduces a cost-effective, facile approach to minimize P to sub-10-nm at a regular substrate temperature, paving the way to study chiral plasmonics approaching the physical limit and exploit chirality-related bioapplications typically operated in aqueous solutions to tackle significant health and environmental problems. Keywords: plasmonic nanoparticles, chiroptical activity, reversible water effect, plasmonic nanospirals, glancing angle deposition

L-05 Self-assembled BiFeO3-ε-Fe2O3 vertical heteroepitaxy for visible light photoelectrochemistry Ying-Hao Chu National Chiao Tung university

Self-assembled vertical heterostructure with a high interface-to-volume ratio offers tremendous opportunities to realize intriguing properties and advanced modulation of functionalities. Here, we design a heterostructure composed of two visible-light photocatalysts, BiFeO3 (BFO) and ε-Fe2O3 (ε-FO), to investigate its photoelectrochemical performance. The structural characterization of the BFO-ε-FO heterostructures confirm the phase separation with BFO nanopillars embedded in the ε-FO matrix. The investigation of band structure of the heterojunction suggests the assistance of photoexcited carrier separation, leading to an enhanced photoelectrochemical performance. The insights into the charge separation are further revealed by means of ultrafast dynamics and electrochemical impedance spectroscopies. This work shows a delicate design of the self-assembled vertical heteroepitaxy by taking the advantage of the intimate contact between two phases that can lead to a tunable charge interaction, providing a new configuration for the optimization of photoelectrochemical cell. Keywords: BiFeO3, photoelectrochemical, water splitting

L-06 Controlled Self-assembly of Porphyrin and Applications Jiefei Wang, Yong Zhong, Yanqiu Liu, Na Zhang, Feng Bai Key Laboratory for Special Functional Materials of the Ministry of Education, Henan University

Porphyrin self-assembly nanomaterials, as visible-light harvesting materials in the artificial photosynthetic systems that mimic natural photosynthesis, have been well designed and developed via molecular self-assembly with non-covalent interactions including electrostatic force, metal-ligand coordination, π-π stacking, hydrogen bonding as well as host-guest interactions[1-5]. And porphyrin self-assembly with well-defined structures have drawn much attention in a wide range of fields including light-energy conversion, photonics as well as photodynamic therapy due to their attractive photophysical, photochemical and electronic properties in the visible-light region. We report a surfactant self-assembly induced micelle encapsulation method to fabricate porphyrin nanocrystals using the optically active precursor zinc porphyrin (ZnTPP). Through confined non-covalent interactions of ZnTPP within surfactant micelles, nanocrystals with a series of morphologies

3 including nanodisk, tetragonal rod, and hexagonal rod, as well as amorphous spherical particle are synthesized with controlled size and dimension[2,3,5]. A phase diagram that describes morphology control is achieved via kinetically controlled nucleation and growth as shown in Figure 1. Due to the spatial ordering of ZnTPP, the hierarchical nanocrystals exhibit both collective optical properties resulted from coupling of molecular ZnTPP and shape dependent photocatalytic activities in photo degradation of methyl orange (MO) pollutants. References 1. Bai F, Sun Z, Wu H et al. Nano Lett. 2011, 11, 3759-3762 2. Bai F, Wu H, Haddad R E et al. Chem. Comm. 2010, 46, 4941-4943 3. Bai, F.; Sun, Z.; Wu, H.; Haddad, R. E.; Coker, E. N.; Huang, J. Y.; Rodriguez, M. A.; Fan, H. Nano Lett. 2011, 11, 5196-5200 4. Zhong, Y.; Wang, Z.; Zhang, R.; Bai, F.; Wu, H.; Haddad, R.; Fan, H. ACS Nano 2014, 8, 827-833. 3. Zhong Y, Wang J, Zhang R et al. Nano Lett. 2014, 14, 7175-7179 Keywords: Porphyrin, Self-assembly, photocatalytic activity

L-07 Fabrication of 6.2% Efficient CZTSSe Solar Cells by two step process Cherng-Yuh Su National Taipei University of Technology

Group I-III-IV2 aspect, the main compound of the CIS solar cells are more common, having a relatively high light absorption coefficient α (104 ~ 105 cm-1). In this study, CZTSSe absorber films were prepared by using DC magnetron sputtering with three different metal targets Cu, Zn and Sn respectively. By depositing to form CZT precursor layer, then under low temperature Sulfurization process and high temperature Selenization process to form Cu2ZnSn (S1-xSex)4 (CZTSSe) film. The impact of using different sulfur and selenide diffusion to the material properties of CZTSSe thin film will be discussed in this study. Furthermore, the surface morphology, crystal structure and optical properties that affect the phenomena to the thin film will be included. Keywords: CZTSSe, Two Step Process, Solar Cells

L-08 N-doped graphene grown on silk cocoon-derived interconnected carbon fibers for oxygen reduction reaction and photocatalytic hydrogen production Yongpeng Lei, Qi Shi, Yingde Wang National University of Defense Technology

Carbon based metal-free catalysts are promising for substitution of rare and expensive platinum (Pt) used in oxygen reduction reaction (ORR). We report an exquisite integration of N-doped graphene (NG) with highly conductive frameworks, in order to provide more active sites and higher conductivity simultaneously. The NG was in-situ grown on silk cocoon-derived carbon fibers (SCCf) via a simple one-step heat treatment. The resulting product (NG-SCCf), possessing meso- /macro-porous structure and 3D interconnected networks, shows an onset potential of only 0.1 V less negative than that of Pt/C, superior stability and methanol tolerance to Pt/C in alkaline media. Moreover, without loading Pt as cocatalyst, the NG-SCCf illustrates a photocatalytic H2 production rate of 66.0 μmol h-1g-1, 4.4-fold higher than that of SCCf. The prominent property is intimately related to the in-situ grown NG, hierarchically porous structure and interconnected 3D networks, not only introducing more active sites but also availing smooth electron transfer /mass transport and effective separation of electron-hole pairs.

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Considering the abundant availability of the green raw in combination with easy and low cost preparation, this work would extend the avenue to advanced and sustainable catalysts for energy storage /conversion fields such as electrocatalysis and photocatalysis. Keywords: N-doped grapheme, silk cocoon, interconnected carbon fibers, oxygen reduction reaction, photocatalytic hydrogen production

L-09 Grain size effects on microstructural stability and creep behavior of nanotwinned Ni free-standing foils at room temperature Jiao Li, Jinyu Zhang, Gang Liu, Jun Sun State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University

Creep tests were performed on the high stacking fault energy (SFE) nanotwinned (NT) Ni free-standing foils with nearly the same twin thickness at room temperature (RT) to investigate the effects of grain size and loading rate on their microstructural stability and creep behavior. The grain growth mediated by the twinning/detwinning mechanism at low applied stresses (< 800 MPa) and grain refinement via the detwinning mechanism at high applied stresses (> 800 MPa) were uncovered in the present NT-Ni foils during RT creep, both of which are attributed to the interactions between dislocations and boundaries. It appears that a higher initial dislocation density leads to a faster primary creep strain rate and a slower steady-state creep strain rate. Unlike the non-twinned metals in which grain growth often enhances the creep strain rate, the twinning/detwinning-mediated grain growth process unexpectedly lowers the steady-state creep strain rate, whereas the detwinning-mediated grain refinement process accelerates the creep strain rate in the studied NT-Ni foils. A modified phase-mixture model combined with Arrhenius laws is put forward to predict the scaling behavior between the creep strain rate and the applied stress, which also predicts the transition from grain growth-reduced to grain refinement-enhanced steady-state creep strain rate at a critical applied stress. Our findings not only provide deeper insights into the grain size effect on the mechanical behavior of nanostructured metals with high SFE, but also benefit the microstructure sensitive design of NT metallic materials. Keywords: Nanotwinned Ni; Creep; Grain growth; Dislocations; Boundary; Size effect

L-10 Cost-effective fabrication of three-dimensional nanopore arrays for hierarchical structured high performance pseudocapacitors Yuan Gao, Yuanjing Lin, Zhiyong Fan Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology

Ordered three-dimensional (3-D) nanopore arrays are regarded as the one of the most promising structures for supercapcitor current collector, mainly due to the facts that i) large surface area for more pseudo-capacitive material deposition; ii) an ordered nanopore structure with uniform pore size can help to improve accessibility of electrolyte to electrodes; iii) 3-D structures can help the materials located on it release mechanical stress. However, nanopore arrays electrode fabrication always involve conductive materials deposition process and conventional physical vapor deposition (PVD) is not suitable for long channel and high aspect ratio deposition due to directionality of the vapor molecules.Besides, the rather high cost and slow deposition rate confines atomic layer deposition (ALD) method in terms of practical application. Here, we report 3-D fluorine doped tin oxide (FTO) nanopore arrays fabricated by a cost-effective ultrasonic spray pyrolysis (USP) method in anodic alumina oxide

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(AAO) channels with high uniformity. The large surface area of such structure leads to remarkable surface area enhancement up to 51.8 times as compared to a planar structure. Combing with electrochemically deposited manganese dioxide (MnO2) nanoflakes on the inner side wall of the FTO nanopores, the unique hierarchical tubular structured pseudocapacitor electrode demonstrated the highest areal capacitance of 193.8 mF cm-2 at the scan rate of 5 mV s-1 and 184 mF cm-2 at the discharge current density of 0.6 mA cm-2, which is 18.5 times of that of a planar electrode. And it also showed a volumetric capacitance of 112.6 F cm-3 at the scan rate of 5 mV s-1 and 108.8 F cm-3 at the discharge current density of 0.6 mA cm-2. In addition, cyclic stability test also indicated that a nanostructured pseudocapacitive electrode has a much larger capacitance retention after 3,000 cycles charge-discharge process as compared with a planar electrode, primarily due to the mechanical stability of the nanostructure. Moreover, pseudocapacitor device fabricated based on such electrodes shows the volumetric capacitance of 17.5 F cm-3, and the highest specific energy of 1.56 × 10-3 Wh cm-3. With the merit of facile fabrication procedures and largely enhanced electrochemical performance, such a 3-D structure has high potency for energy storage systems for a wide range of practical applications. Keywords: pseudocapacitors, hierarchical core-shell structure, manganese dioxide, ultrasonic spray pyrolysis

L-11 Graphene Tribotronics for Touch Sensing Applications Usman Khan Sungkyunkwan University

Here, we demonstrate a graphene based tribotronic transistor for touch sensing applications. The operation of the transistor is based on the coupling of triboelectrification and carrier transport in a graphene channel. When an external object comes into contact with the gate dielectric layer, charges are produced due to the well know triboelectric effect [1]. The triboelectric charges act as a gate bias for the graphene channel and, consequently, modulates its carrier flow. Device characterization shows that the tribotronic transistors exhibits good touch sensitivity with fast response and recovery times; a current change of ~15 uA was observed when touched with a ~ 19N force; the response and recovery times were ~70 ms. The graphene based tribotronic trnasistors possess a crucial advantage over the OTFT based tactile sensing devices [2]. They indeed offer structural simplicity than OTFTs based devices which typically requires additional suspended gates.

1. F.-R. Fan, Z.-Q. Tian, Z. L. Wang, Nano Energy, 1 (2012), 328–334. 2. Y. Zang, F. Zhang, C.-A. Di, and D. Zhu, Material Horizons, 2 (2015), 140. Keywords: Tribotronics; Triboelectrification; Graphene Field Effect Transistor

L-12 Metal oxide/vertically-aligned carbon nanotubes hybrid electrodes for high-performance asymmetric supercapacitor Bin Zhao, Wenkang Zhang, Junye Cheng, Yaolong Yin, Yang Junhe University of Shanghai for Science and Technology

Although much effort has been made to develop high-performance electrode materials, low energy density of supercapacitors is still an obstacle for their practical application. According to equation of energy density E = 1/2CU2, the specific energy of supercapacitors can be enhanced by increasing specific capacitance (C) and/or broadening operating potential window (U).

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3D carbon-based nanostructures, in particular vertically-aligned carbon nanotubes (VACNTs), could be an ideal architecture for electrode materials because of their large specific surface areas, high conductivity, and excellent chemical stability. Moreover, the appropriate intertube spacing among CNTs can ensure the highly efficient transport of electrolytic ions. However, the electrical double-layer capacitance from VACNTs alone could not lead to satisfactory performance. Alternatively, pseudocapacitive metal oxides have attracted great attention due to the large specific capacitance and high energy density. But they often suffer from the poor rate capacity and cycling stability due to the low conductivity. Therefore, the hybrid material with pseudocapacitive metal oxides decorated on VACNTs holds great promise for high-performance supercapacitors. In this work, a facile two-step method was developed to synthesize the metal oxide/VACNTs hybrid electrodes. Firstly, VACNTs were grown on Si substrates with the Al2O3/Fe catalyst by a water-assisted CVD method. Then, the VACNTs were impregnated with nickelocene with the assistance of supercritical CO2. After that, the sample was annealed at temperatures below 400 °C in air to convert the nickel precursor to NiO. From SEM and TEM examination, NiO nanoparticles are found to be uniformly distributed on CNTs and the typical particle size is about 10 nm. Due to the synergetic effects of highly conductive VACNTs and well-dispersed NiO nanoparticles, the VACNTs/NiO hybrid electrode exhibits a high capacitance of 1088.44 F/g. An asymmetric supercapacitor was assembled with the VACNTs/NiO as cathode and the as-grown VACNTs as anode. Remarkably, the energy density of the asymmetric supercapacitor is as high as 90.9 Wh/kg at 3.2 kW/kg and the maximum power density reaches 25.6 kW/kg at 24.9 Wh/kg, which are superior to those of the NiO or VACNTs-based asymmetric supercapacitors. More importantly, the asymmetric supercapacitors exhibit capacitance retention of 87.1% after 2000 cycles at 5 A/g. Besides, VACNTs/Fe2O3 hybrid anode material, which has a negative potential window in KOH electrolyte, was also prepared by the similar method. The VACNTs/Fe2O3 hybrid electrode exhibit a specific capacitance of 248 F/g. And the assembled VACNTs/Fe2O3//VACNTs/NiO asymmetric supercapacitor achieves an extremely high energy density of 137.3 Wh/kg at a power density of 2.1 kW/kg, which still retains 102.2 Wh/kg at the high power density of 39.3 kW/kg. And it also shows an outstanding cycling stability with ～90.1% capacitance retention after 2000 cycles. The facile and effective synthesis method as well as the superior electrochemical performance of the VACNTs/NiO and VACNTs/Fe2O3 composites pave a way for promising application in high-performance energy storage. Keywords: VACNTs, NiO, Fe2O3, Asymmetric supercapacitor, Supercritical CO2

L-13 The preparation of nano-materials Junyu Zhang Verder Shanghai Instruments and Equipment Co., Ltd.

With the intensive application of nano-materials & functional materials, how to apply ultra-fine grinding technology in the production and dispersion of nano-materials has become an important contemporary issue. Usually there are two kind of nano powder methods. The first method is chemical processing so called bottom-up method, such as chemical precipitation, sol-gel method .... The second method is physical processing, where the small powders turned into small particles, such as mechanical milling method. So far, the chemical or mechanical grinding method are the most popular ways to get the batch product of nano-powders. Such as graphene prepared by chemical vapor deposition, mechanical stripping Method to generate black phosphorus-ene. Sometimes the manufacturing cost is so high and so difficult to be massive, and the result of particle size distribution is also too

7 wide. So far, the real production to obtain nano powder based on mechanical grinding method yet. Mechanical grinding method is easier to get the much narrower the particle size distribution of nano powder, while production costs are relatively low, the parameters are easy to control. R & D enlarge lab scale machine to the production application, the sample can be ground to <100 nm, to meet the needs of the industry. Here we discuss the way to get wet milling of nano-scale powder, how to choose a suitable solvent, dispersing agent and drying method then the nano-material can be approached successfully.

L-14 : Concept, Design and Energy Conversion Jian Liu Curtin University

Nanoreactors are a form of chemical reactor that are particularly in the disciplines of and . These special reactors are crucial in maintaining a working nanofoundry; which is essentially a foundry that manufactures products on a nanotechnological scale.1 In this presentation, I will discuss our recent progress toward design of smart nanoreactors for energy applications. The high activities of yolk/shell catalysts have been attributed to the freely movable core catalysts, the hollow space between the core and shell, and the protective shells, which provide a homogenous environment for a heterogeneous catalysis. We have developed novel strategies for the synthesis of yolk-shell structured nanoreactors with controllable sizes, compositions, geometries, structures and functionalities.1-3 At the meantime, the facile synthesis of a yolk–shell catalyst with isolated acidic and basic active sites in one particle (YS-NH2@SO3H) was also realised.4 More importantly, many applications have also been explored (e.g., enzyme catalysis, oxidation of alcohols, Cascade reaction), showing the industrial importance of these materials.1,5 We have also been working on design and synthesis of various nanoporous carbon spheres (NCSs) (including novel microporous carbon spheres, mesoporous carbon spheres, core shell and yolk shell carbon spheres with hierarchical porous structures) with high monodispersity, defined size and orientation of pores, tunable surface area, and controlled surface properties and structural ordering. The loading of Au nanoparticles can be altered from 8 to 44 % in the N-MCN@Au samples. The SEM and TEM images of N-MCN@Au indicate that the amount of Au nanoparticles in each carbon nanosphere increases with increasing concentration of metal salt. Surprisingly, even at metal loading as high as 44% these Au nanoparticles are still uniformly dispersed and spatially separated on the mesoporous carbon support (Figures 1). Catalytic performance of these catalysts was evaluated for hydrogenation of benzaldehyde in water using a high-pressure reactor. In general, hydrogenation of benzaldehyde can generate benzyl alcohol, toluene, benzene and other byproducts due to the competitive hydrogenation between the C=O and phenyl groups. Our carbon spheres with highly dispersed Au catalysts were highly active and chemoselective for hydrogenation towards the C=O group at the room temperature. Our carbon spheres with highly dispersed Au catalysts were highly active and chemoselective for hydrogenation towards the C=O group at the room temperature. In the case of Au catalysts, toluene was the only product at 100% conversion of benzaldehyde. The results are consistent with earlier reports on hydrogenation over gold nanoparticles with sizes of about 5-8 nm. This study shows that the catalytic activity of Pt, which has been considered as the best hydrogenation catalyst, is much lower (turn over frequencies, TOF from 12-14 h-1) than that of the corresponding Au catalysts (TOF from 30-45 h-1) for hydrogenation in water. Our synthesis strategies provide a new benchmark for fabricating smart nanoreactors with a great promise for energy storage and conversion applications. For the first time, we demonstrated that carbon spheres could be impregnated with uniformly dispersed Au and Pt nanoparticles at loadings as high as 44 wt%. A morphology

8 dependent catalysis on Au nanoparticles was found for hydrogenation of benzaldehyde at room temperature, in which the highest activity (TOF 3-4 times higher than that on the Pt particles with the same size and metal loading) and selectivity (100% to toluene).

References 1. J. Liu et al., Chem. Commun., 47, 12578 (2011) 2. J. Liu et al., Angew. Chem. Int. Ed. 49, 4981(2012) 3. J. Liu et al., Adv. Funct. Mater. 22, 591 (2012) 4. Y. Yang et al., Angew. Chem. Int. Ed. 51, 9164 (2012) 5. Z.Y. Zhao et al., RSC Advances, 3, 22008(2013) 6. J. Liu et al., Nat. Mater., 14, 763(2015) 7. J. Liu et al.,Angew. Chem. Int. Edit., 50, 5947 (2011) 8. T. Yang et al.,Chem. Commun. 51, 2518(2015) 9. J. Liu et al., Nature Commun. 4, 2798 (2013) 10. T. Yang et al., NPG Asia Mater., 8, e240 (2016) Keywords: Nanomaterials; Energy conversion; Catalysis

L-15 High-output Current Density of the Triboelectric Nanogenerator Made from Recycling Rice Husks Jyh-Ming Wu National Tsing Hua University

This work, we are the first to discover a high short-circuit current density of triboelectric nanogenerator using recycling rice husks as a source material. After leached the rice husks in hydrochloric acid (HCl) solution and calcined them at 700 °C for 3 hr, the purely nanoporous silica powder with pore sizes around 20 – 40 nm could be produced, as denoted by RHSiO2. The structure of the pores and pore size distribution are greatly dominated by the nature of the raw rice husks. Such nanoporous structures with greatly positively charged surfaces are highly distributed throughout the rice-husk SiO2 (RHSiO2) fragments. Thus, the nanoporous RHSiO2 and untreated polytetrafluoroethylene (PTFE) films are served as two dielectric layers of TENG at the opposite ends of the triboelectric series. On the basis of our FTIR spectra, the nanoporous RHSiO2 fragments offers highly dense Si-O-Si, Si-OH, and OH stretching bonds compare to commercial SiO2 nanoparticles. The RHSiO2 film therefore exhibits strongly tendency to repel the electron because the H atoms have an extremely low electron affinity compared to the PTFE film. The highly positively charged surfaces of the nanoporous RHSiO2 film is five times higher than that of commercially non-porous SiO2 film based on our theoretical calculated results. Keywords: Rice Husks, Triboelectric Nanogenerator

L-16 High-Performance Photovoltaic Devices with Advanced Nanotechnology Feng Yan Department of Applied Physics, The Hong Kong Polytechnic University

High-performance organic solar cells have been developed by our group based on various nanotechnology in recent years. First, the efficiency of organic solar cells have been improved by introducing plasmonic nanoparticles,[1] high mobility conjugated polymers[2] or 2-D materials.[3] Pronounced effects have been

9 observed in the devices due to the improvement of the carrier mobility or light absorption in the active layer. Graphene has shown promising applications in photovoltaic devices for its high carrier mobility and conductivity, high transparency, excellent mechanical flexibility and ultrathin thickness and can be used in solar cells as transparent electrodes or interfacial layers.[4] Package-free flexible organic solar cells are fabricated with multilayer graphene as top transparent electrodes,[5] which show high power conversion efficiency, excellent flexibility and bending stability. Semitransparent organic solar cells and perovskite solar cells were prepared by using graphene transparent electrodes.[6] For the perovskite solr cells, the devices show high power conversion efficiencies (~12%) when they are illuminated from both sides. Considering the poor stability of perovskite solar cells in ambient air especially with high humidity, we have recently developed a novel technique to improve the device stability by introducing SCN- to partialy replace I- in the perovskite material, which can dramatically improve the lifetime of package-free device in air.[7] All of the techniques will be very useful for the practical applicaitons of the novel photovoltaic devices. References 1. S. H. Liu et al. Energy Environ. Sci. 9, 898-905 (2016). 2. S. H. Liu, et al. Energy Environ. Sci. 8, 1463-1470 (2015). 3. S. H. Lin, et al. Adv. Funct. Mater. 26, 864-871 (2016) 4. Z. K. Liu, et al. Chem Soc. Rev. 44, 5638-5679 (2015). 5. Z. K. Liu, et al. Adv. Mater. 25, 4296-4301 (2013). 6. P. You, et al. Adv. Mater. 27, 3632-3638 (2015). 7. Q. D. Tai, et al. Nature Comm. 7:11105 (2016). Keywords: organic solar cell, perovskite solar cell, graphene,

L-17 Multifunctional Electronic Skins for Wearable Sensors Jonghwa Park, Minjeong Ha, Youngoh Lee, Hyunhyub Ko* Ulsan National Institute of Science and Technology

Flexible electronic skins with high tactile sensitivities have gained great attentions in the fields of wearable sensors, robotic skins, and biomedical diagnostics. In human fingertip skin, the fingerprint patterns and interlocked epidermal-dermal microridges have critical roles in amplifying and transferring the tactile signals to various mechanoreceptors, enabling the spatio-temporal perception of various static and dynamic tactile signals. Here, mimicking the structures and functions of fingertip skin, we introduce highly-sensitive, multifunctional, and stretchable electronic skins. Inspired by the interlocked microstructures found in epidermal-dermal ridges in human skin, piezoresistive interlocked microdome arrays are employed for stress-direction-sensitive, stretchable electronic skins. We show that the interlocked microdome arrays possess highly direction-sensitive sensitive detection capability of various mechanical stimuli including normal, shear, stretching, bending, and twisting forces. We also demonstrate that the ferroelectric skins with fingerprint-like patterns and interlocked microstructures can detect and discriminate multiple spatio-temporal tactile stimuli including static and dynamic pressure, vibration, and temperature with high sensitivities. In addition, we demonstrate that the bioinspired e-skin design of hierarchical micro- and nanostructured ZnO nanowire arrays in an interlocked geometry shows a highly-sensitive detection of both static and dynamic tactile stimuli through piezoresistive and piezoelectric transduction modes, respectively. Finally, we show that the stretchable electronic skins attached on the human skin can be used as wearable healthcare monitoring devices, which are able to distinguish various mechanical stimuli

10 applied in different directions, selectively monitor different intensities and directions of air flows and vibrations, and sensitively monitor human breathing flows and voice vibrations. In addition, dynamic touch sensing ability is employed for precise detection of acoustic sounds, and discrimination of various surface textures. Keywords: Electronic skin, Tactile sensor, Biomimetic, Piezoresistive, Piezoelectric

L-18 High Performance Piezoelectric Power Generation from Atomic-layered MoS2 by Sulfur Vacancy Passivation Tae-Ho Kim, Sang A Han, Sang-Woo Kim Sungkyunkwan University

The piezoelectric characteristic of two-dimentional materials are of great interest as high-performance piezoelectric potential applications. In order to practical applications, CVD based large area monolayer MoS2 is essential. However CVD based MoS2 has the intrinsic defect such as sulfur vacancy during the growth process and those defect plays and important role in screening the peizoelectric potentail. So only small peizoelectric potential induced power output observed from CVD grown MoS2. Here we demonstrate high performance piezoelectric nanogenerator using CVD based monolayer MoS2 nanosheet by additional sulfur treatment process during MoS2 growth process. The measured piezoelectric coeffecient (d11) of CVD grown large area monolayer MoS2 nanosheet is 3.73 pm V-1 using lateral PFM methods, and it generates a peak power density of a 0.8 mW which is 10 times higher than that of as-grown monolalyer MoS2 nanosheet. Also to improve the reason why additoinal sulfur treated monolayer MoS2 nanosheet shows enhanced piezoelectric characteristics, XPS, PL and KPFM anylysis was performed. Keywords: Molybdenum disulfide, piezoelectricity, nanogenerator, sulfur vacancy, passivation

L-19 Low-dimensional III-V Materials for Infrared Photodetection Jiang Wu University College London

Infrared photodetectors can be applied to various applications in both military and civil sectors, including chemical sensing, night vision, and surveillance. The demand in high performance third generation infrared photodetectors has driven the development of low-dimensional III-V nanomaterials as infrared photon absorber. Particularly, the mature III-V technology can potentially realize large format infrared focal plane arrays with high performance. While III-V nanomaterials have shown promising results in the last two decades, the hetero-integration of detectors and Si-based readout integrated circuits involves complicated processing steps and undermines the yield of focal plane arrays. In this talk, we present the growth of quantum structured III-V materials infrared on Si substrates. High quality III-V quantum dots and strained type II superlattices can be obtained on Si substrates with proper buffer layers by using molecular beam epitaxy. The demonstration of III-V infrared photodetectors on Si substrates will benefit from the mature Si process technology and enable low cost and large format infrared focal plane arrays for both civil and military applications. Keywords: quantum dots; type II superlattices; infrared; III-V

L-20 Radiopacity Improvement of Nanocrystalline Zr/Bi Oxide Composite Powder Prepared by Wet Processes

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Chung-Kwei Lin Bismuth oxide is rare-earth metal oxide with a melting point of 824 oC. There are various polymorphic materials of bismuth oxide that can be used as solid electrolyte and photocatalyst. In addition, bismuth oxide also a major constitute of mineral trioxide aggregate (MTA) and serves as radiopacifier within MTA. The R&D trends of MTA mainly focus on its constitution, biocompatibility, physical and chemical properties, and its setting time, etc.. There are still increasing R&D interests concerning the basic and clinical application of MTA. Concerning the replacement of bismuth oxide, zirconium oxide with its excellent mechanical properties and biocompatibilities is among the best potential material. Composite bismuth oxide and zirconium oxide powder prepared by ball milling process has revealed compatible radiopacifying ability with its commercial prototype. In the present study, composite bismuth oxide and zirconium oxide powder was by wet process including sol-gel and precipitation methods. The as-prepared composite powder was heat treated at various temperature to further improve the radiopacity of composite powder. The optimum composite composition will be mixed with Portland cement to investigate its radiopacifying performance. Experimental results showed that a significant improvement in radiopacity can be achieved using nanocrystalline composite powder prepared by wet process and followed by suitable post heat treatment. Keywords: dental filling material, rediopacity, bismuth oxide, zirconia, composite, sol-gel, precipitation

L-21 X-ray synthesis and imaging of nanoparticles Yeu-Kuang Hwu Academia Sinca

The high brightness x-ray sources directed the development of x-ray microscopy toward excellent spatial resolution and other performance. However, practically achieving nanometer scale resolution poses formidable technology challenges. The technology to focus hard-X-rays (photon energy larger than 1–2 keV) has made great progress in the past decade. The progress was particularly spectacular for lenses based on the Fresnel zone plate (FZP) concept. Fresnel zone plates (FZPs) are widely used as focusing and magnifying optics devices and offer the highest imaging resolution and consequently opening up entirely new domains of application, specifically in materials and biomedical research. The inaugurations of the new generation synchrotron and X-ray Free Electron Laser facilities mark an important milestone on the development of X-ray science. The impact of these new facilities to the nanoscience and nanotechnology is also become visible. The speaker will use two examples, to suggest the bright potential of X-rays imaging, which is an area taking full advantage of the offer of these new opportunities. One the application synchrotron X-rays, phase contrast imaging and transmission X-ray microscopy demonstrate the capability to impact life science by tackle important questions, such as the tumor related micro-angiogenesis. With the capability to characterize quantitative all the structural factor of the microvasculature of complete tumor region or an organ, aided with the innovative use of nanoparticles, we could conclude that the phenotype dependent tumor angiogenesis in mouse glioma models. We also used the SACLA (RIKEN/HARIMA, Japan) X-ray free electron laser (X-FEL) to implement coherent diffraction imaging (CDI) of individual liposome particles in water, with or without inserted doxorubicin nanorods. In spite of the low cross section, the diffracted intensity of blank (drug-free) liposomes was sufficient for spatial reconstruction yielding quantitative structural information. When the particles contained doxorubicin, we could measure the structural parameters of the nanorods. In both cases, the information went well beyond what can be obtained by small-angle X-ray scattering (SAXS) and electron microscopy. This is important for the potential drug

12 efficiency optimization and, in general, for X-FEL analysis of individual low-cross-section nanoparticles. Keywords: X-ray imaging, nanoparticles, photoluminescence

L-22 Electronic properties of phosphorene nanoribbons with periodically punched nanoholes Lin Sun1, Hao Wang2, Mo Li1,3 1. College of Physics and Electronics, Central South University 2. College of Mechatronics and Control Engineering, Shenzhen University 3. School of Materials Science and Engineering, Georgia Institute of Technology

Using the first-principles method based on the density-functional theory and nonequilibrium Green’s function, electronic properties of monolayer black phosphorus nanoribbons (PNRs) punched with periodic nanoholes (PNRPNHs) and the stability of the structure are studied systematically. It is shown that the PNRs with nanoholes and the perfect PNRs possess similar properties as semiconductors no matter they are armchair-edge PNRs or zigzag-edge PNRs. However, the punched nanoholes can change the electronic structure of the PNRs. For example, though still being semiconductor, the zigzag-edge PNRPNH undergoes a direct-to-indirect bandgap transition. However, the armchair-edge PNRPNH still remains a direct bandgap but the bandgap significantly increases as compared with the perfect PNRs. With calculating the binding energy, we find that the influence of nanoholes on the stability of PNRs is very small, only slightly lower than the perfect PNRs. In addition, as compared with the perfect PNRs, the applied external transverse electric field and strains can more effectively modulate the bandgaps of PNRPNHs,, making it reduced with the increase of the applied external transverse electric field strength. These novel electronic properties suggest that PNRs is a promising candidate for future nanoelectronic and optoelectronic applications. Keywords: phosphorene nanoribbons, periodic nanoholes, electronic properties, binding energy

L-23 Synthesis of core-shell structured magnetic nanospheres with controllable outer layer Shushan Hou Changchun University Of Technology

Core-shell structured materials combining the functionalities of the core and shell have great application potential in various fields. In this work, by combining solvothermal method and the sol-gel method, we have successfully developed a core-shell structured microspheres which possess an internal magnetic particle and an outer shell of phenolic resin/carbon. The thickness of phenolic resin/carbon shell could be easily tuned by changing the time of carbonizatin. The resulting microspheres possess well-defined structure, uniform sizes, high magnetization, controllabe outer shell thickness (50-150nm). The unique nanostructure of the magnetic core-shell structured microspheres could lead to many promising applications in areas ranging from drug delivery to the purification of sewage. Keywords: solvothermal method; sol - gel method; template method; core-shell structure; magnetic materials.

L-24 ZnO nanowire LED arrays for visual strain/pressure mapping by piezo-phototronic effect Caofeng Pan 1. Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, China, 100085

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2. School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0245

In this talk, we present a novel design of nanowire LED arrays, which can be used to directly record the strain distribution by piezo-phototronic effect, which is published in Nat. Photonics, Adv. Mater. et al. In our group, we have firstly demonstrated how the piezo-phototronic effect can be effectively utilized to enhance the emission intensity of an n-ZnO/p-GaN NW LED (Nano Letters 11, 4012(2011), Nano Letters 13, 607(2013)). The emission light intensity and injection current at a fixed applied voltage has been enhanced by a factor of 17 and 4 after applying a 0.1% compressive strain, respectively. Here, we extend the single NW device to NW LEDs array, for pressure/force sensor arrays for mapping strain with a resolution as high as 2.7 μm (Nature Photonics 7, 752(2013)). Such sensors are capable of recording spatial profiles of pressure distribution, and the tactile pixel area density of our device array is 6250000/cm2, which is much higher than the number of tactile sensors in recent reports (~ 6-27/cm2) and mechanoreceptors embedded in the human fingertip skins (~ 240/cm2). When the device is under pressure, the images unambiguously show that the change in LED intensity occurred apparently at the pixels that were being compressed by the molded pattern, while those were off the molded characters showed almost no change in LED intensity. Instead of using the cross-bar electrodes for sequential data output, the pressure image is read out in parallel for all of the pixels at a response and recovery time-resolution of 90 ms. Furthermore, our recent studies achieve such piezo-phototronic effect induced strain mapping in a flexible n-ZnO NWs/p-polymer LEDs array system. This may be a major step toward digital imaging of mechanical signals by optical means, with potential applications in touch pad technology, personalized signatures, bio-imaging and optical MEMS. Furthermore, this piezo-phototronic effect was achieved on p-Si/n-ZnO LED array (Advanced Materials 27, 4447(2015)) and p-PSS:PEDOT/n-ZnO NW LED array(Advanced Functional Materials 25, 2884(2015)). By applying a strain onto the top of the LEDs, the light emission intensity of LEDs array was enhanced as well by 120% under -0.05% compressive strains. A pressure map can be created by reading out in parallel the change of the electroluminescent intensities from all the pixels in the near future. This research not only introduce a novel approach to fabricate Si-based or polymer-based flexible light-emitting components with high performances, but also may be a great step toward digital imaging of mechanical signals using optical means, having potential applications in artificial skin, touch pad technology, personalized signatures, bio-imaging and optical MEMS, and even and smart skin. Moreover, these are totally compatible with the dominate silicon microelectronic industry, which means large-scale integrated device could be easily achieved for future assembling in silicon-based photonic integrated circuits (PIC) and optical communication systems.

L-25 Solar Energy Harvesting Scheme Utilizing Low Dimensional Micro- and Nano-structures Yu-Lun Chueh National Tsing Hua University

In this talk, I will introduce the development of low dimensional nanomaterials in my group and its applications on Cu(In, Ga)Se2 solar cell. The direct formation of large area Cu(In,Ga)Se2 nanotip arrays (CIGS NTRs) by using one step Ar+ milling process without template. By controlling milling time and incident angles, the length of CIGS NTRs with adjustable tilting orientations can be precisely controlled. Formation criteria of these CIGS NTRs have been discussed in terms of surface curvature, multiple components, and crystal quality, resulting in a highly anisotropic milling effect. In addition to physical approach to form nanostructures on the CIGS film, a

14 reactive mold-assisted chemical etching (MACE) process through an easy-to-make agarose stamp soaked in bromine methanol etchant to rapidly imprint larger area micro- and nano- arrays on CIGS substrates was demonstrated in my group. Interestingly, by using the agarose stamp during the MACE process with and without additive containing oil and triton, CIGS microdome and microhole arrays can be formed on the CIGS substrate. Final part of my talk, i will introduce Au NPs to achieve efficiency enhancement of CIGS flexible photovoltaic devices. The incorporation of Au NPs can eliminate the obstacles in the way of developing ink-printing CIGS flexible TFPV, such as the poor absorption at wavelengths in high intensity region of solar spectrum, and that occurs at large incident angle of solar irradiation. The enhancement of external quantum efficiency and photocurrent have been systematically analyzed via the calculated distributions of electric field. Finally, the major benefits the LSPR in shorter wavelength have been investigated by ultrabroadband pump-probe spectroscopy, which gives a solid evidence on the strong absorption and reduction of surface recombination that increases electron-hole generation and improves the carrier transportation in the vicinity of pn-juction. These results suggest a promising way for rapidly improving the performance of CIGS flexible photovoltaic devices with low-cost. Keywords: CIGS, Solar cell, microstrucutre, nanostructure

L-26 Ions Exchange Reactions on Nanocrystals: Surface/Interface, Doping Control and New Energy Applications Jiatao Zhang Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications， School of Materials, Beijing Institute of Technology

The key iusses of Metal/seminconductor binary cooperative nano-system is the coherence between near field enhancement from localized SPR effect and exciton bohr radius related quantum confinement effect at the nanoscale. To achieve flexible coupling between Plasmon and excition and then enhance optoelectronic applications, the synergistic tailoring of shape, size, composition, crystallization, hetero-interface and the distance between two nanoscopic components comparable to the characteristic length of plasmon/exciton interactions are key materials issues. By controlling soft acid-base coordination reactions between molecular complexes and colloidal nanostructures, we showed that: i) proposed the new synthesis method, namely different kinds of phosphine initialized cation exchange reactions, to precisely synthesize metal/semiconductor hetero-nanostructures and doped semiconductor nanostructures; ii) realized synergistic tailoring on morphologies, compositions and hetero-interfaces of many kinds of metal@monocrystalline semiconductor core/shell nanocrystals and the exploration of their photochemical energy conversion applications; iii) developed the new cation exchange strategy to realize the successive control of substitutional heterovalent doping, surface/interface control, doped luminescence and p-/n-type electronic impurities in semiconductor nanostructures, and explored their photoelectric conversion applications. Keywords: Inorganic synthetic nanochemistry; ion exchange reaction; hetero-nanostructures; metal/semiconductor; doped nanocrystals; new energy;

L-27 Negative-pressure induced enhancements in freestanding nanoferroelectrics jin wang Division of Energy and Environment in Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China

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Ferroelectrics are widespread in technology, with a strong presence in electronics and communications, medical diagnostics and industrial automation, and are entering into the fields of solar and vibrational energy harvesting. Currently there is a substantial interest in extension of their operational temperature-range and exploitable properties. Strain is known to influence ferroelectric properties. Thus, recent developments exploit ultrathin epitaxial films on lattice-mismatched substrates, imposing tensile or compressive biaxial strain to enhance the development of structural order parameters that characterize ferroelectrics. Much larger hydrostatic compressive stress is provided by diamond anvil cells, but its partner, hydrostatic tensile stress, is generally regarded as unachievable. Theory and ab-initio treatments [1] predict enhanced tetragonality, polarisation, and Curie temperature for perovskite ferroelectrics under tensile stress. Here we report the realization of a tensile-stress driven enhancement of the tetragonality, accompanied by strong enhancement in Curie temperature and doubling of the spontaneous polarization in freestanding monocrystalline PbTiO3 nanowires [2], driven by stress that developes during transformation of the material from a lower-density crystal structure to the ferroelectric perovskite phase. The enhancements are maintained for years without degradation. The study also suggests a simple preparation route to obtain built-in negative pressure in numerous other functional materials, potentially extending their exploitable properties far beyond their current levels. [1] Anomalous enhancement of tetragonality in PbTiO3 induced by negative pressure. Tinte, S. et al., Phys. Rev. B. 68, 144105 (2003). [2] Negative-pressure-induced enhancement in a freestanding ferroelectric, Wang J. et al., Nature Materials, 14, 985 (2015). Keywords: ferroelectric nanomaterials, negative pressure, property enhancement

L-28 High Performing Nanocomposite System Based Triboelectric Nanogenerator with Tuned Ferroelectric Property Hongjoon Yoon, Wanchul Seung, Sang-Woo Kim Sungkyunkwan University

Low output current represents a critical challenge that has interrupted the use of triboelectric nanogenerators (TNGs) in a wide range of applications as sustainable power sources. Many (e.g., operation at high frequency, parallel stacks of individual devices, and hybridization with other energy harvesters) have been conducted to solve the challenge of low output current from TNGs. Here, we report a nanocomposite material system having a superior surface charge density as a triboelectric active material. The nanocomposite material consists of a high dielectric ceramic material, barium titanate (BTO), showing great charge-trapping capability, together with a ferroelectric copolymer matrix, Poly(vinylidenefluoride-co-trifluoroethylene) (P(VDF-TrFE)), with electrically-manipulated polarization with strong triboelectric charge transfer characteristics. Based on a contact potential difference (CPD) study showing that poled P(VDF-TrFE) has 18 times higher charge attracting properties, we optimized a fraction (wt.% of embedded nano-sized dielectric particles) between two components. We successfully achieved high power performance boosting up to 1130 V of output voltage and 1.5 mA of output current with this ferroelectric composite system based TNG, under 6 kgf of pushing force at 5 Hz. Additionally, we demonstrated an enormously faster charging property (8 times) than traditional polymer film-based TNGs. Finally, we successfully demonstrated the charging of a self-powering smartwatch with a charging management circuit system without any help of external power sources. Keywords: Triboelectric Nanogenerator, Nanocomposite, Ferroelectric, Dielectric

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L-29 Layer-structured Thermoelectric nanomaterials: Fundermental, Design and Progress Zhigang Chen The University of Queensland

Layer-structured thermoelectric nanomaterials (such as Bi2Te3 and Cu2Se), as ideal thermoelectric candidates for room temperature and intermediate temperature applications, have been considered the most important thermoelectric materials in this field and show great potential on thermoelectrics. However, further improve their thermoelectric performance have been a current global research focus, which needs innovative strategies. In this presentation, through employing bandgap engineering and nanostructural engineering, we summaries our recent findings on a range of layer-structured thermoelectric nanomaterials with improved thermoelectric properties [1-13]. References [1] Z.-G. Chen, C. Zhang, Y. Zou, E. Zhang, L. Yang, M. Hong, F. Xiu and J. Zou, Nano Lett., 2015, 15, 5830-5834. [2] Y. Zou, Z. G. Chen, F. T. Kong, J. Lin, J. Drennan, K. Cho, Z. C. Wang, J Zou, ACS Nano 2016, 10, 5507. [3] M. Hong, T. Chasapis, Z. G. Chen, L. Yang, M. Kanatzidis, G. J. Snyder, J. Zou; ACS Nano 2016, 10, 4719. [4] L. Yang, Z. G. Chen, G. Han, M. Hong, J. Zou; Acta Mater. 2016, 113, 140. [5] M. Hong, Z. G. Chen, L. Yang, J. Zou; Nanoscale 2016, 8, 8681. [6] M. Hong, Z. G. Chen, L. Yang, J. Zou; Nano Energy 2016, 20, 144. [7] L. Yang, Z. G. Chen, T. X. Nie, G. Han, Z. Zhang, M. Hong, K. L. Wang, J. Zou; J. Mater. Chem. C 2016, 4, 521. [8] L. Yang, Z. G. Chen, M. Hong, H. Han, J. Zou; ACS Appl. Mater. Interf. 2015, 7, 23694. [9] L. Yang, Z. G. Chen, H. Han, M. Hong, Y. C. Zou; J. Zou; Nano Energy 2015, 16, 367. [10] Y. C. Zou, Z. G. Chen, J. Lin, X. H. Zhou, W. Lu, J. Drennan, J. Zou; Nano Res. 2015, 8, 3011. [11] M. Hong, Z. G, Chen, L. Yang, G. Han, J. Zou; Adv. Electro. Mater. 2015, 1, 1500025. [12] G. Han, Z. G. Chen, J. Drennan, J. Zou; Small 2014, 14, 2747. [13] Z.-G. Chen, G. Han, L. Yang, L. Cheng and J. Zou, Progress in Natural Science-Materials International, 2012, 22, 535-549. Keywords: thermoelectric nanomaterials

L-30 Electrocatalytical Property of Hybrid Pd/Polyaniline/AO-MWCNTs Nanomaterials for Direct Formic Acid Fuel Cells Yuh-Jing Chiou, Meng-Yuan Chung, Hong-Ming Lin, Andrzej Borodzinski, Leszek Stobinsk Tatung University

DFAFCs (direct formic acid fuel cells) can be a promising green energy. In order to promote the efficiency of DFAFCs, the prepared nano palladium catalyst should have good electrocatalytic performance and stability to be applied as anodic catalyst for formic acid oxidation. In our previous study about direct formic acid fuel cells (DFAFCs), the anodic electrocatalyst palladium is supported by acid treated multi-walled carbon nanotubes (AO-MWCNTs). The defects on AO-MWCNTs can cause the electron captured and reduce both the catalyst conductivity and the electrocatalytic performance. In order to improve the conductive properties, a conductive polymer is introduced to modify the surface of carbon nanotubes. Polyaniline (PANI) has a long-chain conjugated

17 structure and exhibits good conductivity, high stability, and non-toxic. After PANI modification, AO-MWCNTs can provide efficient catalytic reactions conduction electrons and protons network. In this study, polyaniline modified MWCNTs were prepared via interfacial polymerization process in various PANI to AO-MWCNTs weight ratios. Three metal catalyst synthesizing methods, x-ray photosynthesis, NaBH4 reduction and polyol method, were applied to deposit Pd or AuPd nanoparticles on PANI modified AO-MWCNTs. The composition, structure and morphology were confirmed by Raman、TGA、FTIR、XRD、SEM、HRTEM, and ICP. The synthesized PANI is successfully coated on MWCNTs to form a 3-6nm thin film in an optimal PANI/AO-MWCNTs ratio 20/80. The particle size of Pd or AuPd metal is around 1~10 nm. The electrocatalytical analysis indicated the sample Pd/(PANI/AO-MWCNTs)-(20/80) synthesized by x-ray irradiation have the best performance. The results of this study show that the modification of PANI can enhance the conductivity and promote the electrocatalytic performance in direct formic acid fuel cells (DFAFCs). Keywords: DFAFCs, Pd, PANI, x-ray irradiation, MWCNTs

L-31 R&D of Dielectric Barrier Discharge Plasma-assisted Milling in Energy Storage Materials liuzhang ouyang School of Materials Science and Engineering, South China University of Technology

Conventional ball milling is widely used both in commercial application and in research works, but it has numerous drawbacks like long duration, low efficiency, high-energy consumption and serious contamination, which severely confines its industrial application. Dielectric barrier discharge plasma-assisted milling (P-milling), which is a combination of dielectric barrier discharge plasma (DBDP) with high energy ball milling, can effectively promote the procedures of powder refinement, catalysis activation and solid-state reaction due to the synergetic effect of high-energy electron impact, hot from plasma and mechanical energy from ball milling system. Thus this new technique shows great advantages and new phenomena in synthesizing energy storage materials including lithium ion batteries, super-capacitor, hydrogen storage and nickel/metal hydride batteries. We will firstly introduces the basic principles of DBDP and P-milling, and explains the superiority of this new method. Then few-layer graphene sheets (FLG), composites (Ge@FLG, Si@FLG, Sn@FLG, SnO2@FLG and Fe2O3@FLG) prepared through P-milling, and their applications in lithium ion batteries, hydrogen storage, Ni-MH batteries and super-capacitor are also presented. These materials have a special core-shell structure with nanoparticles wrapped by FLG sheets, which shows higher capacity and excellent cycling stability as electrode materials. Furthermore, this paper also reviews the recent progress on the application of P-milling in preparing solid solution and intermetallic compounds for hydrogen storage. Lastly, the influence of P-milling on WC synthesis and its applications are also discussed. P-milling offers a simple, cost effective and pollution-free way for preparing energy storage materials, which may have a large potential in the large-scale production of high performance energy storage materials in the future. Keywords: dielectric barrier discharge plasma (DBDP), energy storage, few-layer graphene sheets (FLG), lithium ion batteries, hydrogen storage

L-32 Synthesis and Characterization of Pd based/MOS/MWCNTs Hybrid Materials for Direct Formic Fuels Cells Hong-Ming Lin1*, Cheng-Hung Yu1, Yuh-Jing Chiou1, Andrzej Borodzinski2, Leszek Stobinski3

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1. Tatung University 2. Polish Academy of Sciences 3. Warsaw University of Technology

For the applications of direct formic acid fuel cell, Pd catalyst with some modification attracts the study attention for its electrocatalytic advantages. To benefit the catalytic performance and prevent the catalyst poison problem, this study develops Pd basis catalysts, which have solid solution phase with Au and metal oxide modified MWCNTs substrate, by impregnation, polyol and X-ray irradiation methods. Metal oxides, CeO2, NiO, In2O3, TiO2, and bioxides, rare earth doped CeO2, SnO2/TiO2, N-doped TiO2 system had been applied to enhance the electrocatalytic activity. However, metal oxide is semiconducting and has low electric conductivity. The noble metal nanoparticles deposited on the surface of a thicker metal oxide layer or larger metal oxide particles, which may be useless due to poor conductivity. To prevent the conductivity effects on cell performance, the high conductivity metal oxides, like In2O3 or ITO, and nitrogen doping TiO2 have been choice to in our study. In this study, bioxides with nitrogen doping and MWCNTs are applied as supporter for Pd and Pd based catalyst to examine its electrochemical performance. In this study, TiO2/MWCNTs is synthesized by sol-gel method. Tin dioxide- (SnO2/CNT) were synthesized by a chemical-solution route. The composite structural properties enhance the surface-to-volume ratio of SnO2 demonstrating a desirable electrochemical performance for anode. The SnO2 and MWCNTs interactions were characterized by X-ray diffraction (XRD). Also, ammonium is used to dope nitrogen into TiO2 to modify its electrical and chemical property. MWCNTs, TiO2/MWCNTs, N-TiO2/MWCNTs, TiO2/SnO2/MWCNTs and N-TiO2/SnO2/MWCNTs are five supporters using in this study to examine the effects of supporters on the electrocatalytic performance of Pd and AuPd catalysts. The synthesized metal nanoparticles are uniformly dispersed on the surfaces of MWCNTs, TiO2, N-TiO2, TiO2/SnO2 and N-TiO2/SnO2 modified MWCNTs. In electrochemical analysis of Pd-series and AuPd series electrocatalysts, Pd/N-TiO2/SnO2/MWCNTs have the highest electro-oxidizing current density. But chronoamperometry analysis indicates Pd on N-TiO2/MWCNTs has the best reliability related the other hybrid catalysts in this study. It may due to N-MOS may enhance Pd on the electrooxidation reaction of formic acid. According to present results, N-doped TiO2 nanoparticles is a strong oxygen promoter to reactivate Pd poisoning surface and MWCNTs can be a good support for metal oxide and Pd based nanoparticles to enhance the formic acid electro-oxidation and carbon monoxide oxidation. Keywords: Formic acid, fuel cells, Pd, TiO2, SnO2, MWCNTs, electrocatalyts

L-33 Piezophototronic Devices Junyi Zhai Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences

Multifunctional micro/nano devices and systems are of important applications in smart electronics for health care, human-machine interfacing, infrastructure monitoring and security. In recent years, piezophototronic effect is developed fast since it offers a new method to improve/tune the optoelectronic properties dramatically. The key characteristic of the piezo-phototronic effect is that the carrier generation, transport, separation and/or recombination at the heterojunction/interface can be tuned by modulating the piezopotential which created and further tuned by externally applied strain. Therefore, one method to enhance piezo-phototronic effect is increasing piezoelectric charge at the interface. Another method to improve piezo-phototronic effect is reducing charge carrier recombination probability, the design of semiconductor composites heterojunction/interface should take

19 into account their band positions and band gap. By interface engineering the p-n junction, piezo-phototronic effect can be improved. Piezophototronic effect can enhance the sensitivity of photodetector dramatically. Here, we show a self-powered GaN flexible film-based metal-semiconductor-metal (MSM) UV photoswitch. The asymmetric MSM structure was designed to suppress carrier recombination and enhance carrier transport. At self-powered condition (no external bias voltage), its UV on/off ratio reaches up to 4.67*105 with high reliability of on/off switching response. Also its UV detection shows an excellent sensitivity (1.78*1012 cmHz0.5W-1). In particular, strain modulation can improve the UV on/off ratio (~154%) by piezo-phototronic effect. Besides photoelectric conversion and electroluminescence, photoluminescence can be tuned by piezoelectric charge as well. Here have developed a new method of pressure sensing by using pressure/strain induced piezoelectric charge to tune PL intensity of InGaN/GaN MQW under small strain (0~0.15 %). Such modulation effect is distinct, linear and ultrafast. Based upon it, an all optical pressure sensor array by the piezo-phototronics effect has been developed to measure dynamic pressure distribution without the need of electricity. Beyond the limitations of electrical connection, our all-optical device offers a novel and suitable way for large-area, high-uniform, high resolution, ultrahigh speed pressure/strain distribution sensing. 1. F. Xue, L.B. Chen, J. Chen, J.B. Liu, L.F. Wang, M.X. Chen, Y.K. Pang, X.N. Yang, G.Y. Gao, J.Y. Zhai*, Z.L. Wang*, Advanced Materials, Accepted 2. M.Z. Peng, Y.D. Liu, A.F. Yu, Y. Zhang, C.H. Liu, J.Y. Liu, W. Wu, K. Zhang, X.Q. Shi, J.Z. Kou, J.Y. Zhai*, Z.L. Wang*, ACS Nano, 2016, 10(1), 1572-1579 3. M.Z. Peng, Z. Li, C.H. Liu, Q. Zheng, X.Q. Shi, M. Song, Y. Zhang, S.Y. Du, J.Y. Zhai*, Z.L. Wang*, ACS Nano, 2015, 9(3), 3143-3150 4. M.Z. Peng, Y. Zhang, Y.D. Liu, M. Song, J.Y. Zhai*, Z.L. Wang*, Advanced Materials, 2014, 26, 6767-6772 Keywords: optoelectronics; piezoelectric; piezo-phototronics

L-34 Controlled Growth of Flexible SiC Field Emiitters and Their Electron Emission Properties Shanliang Chen, Weiyou Yang Ningbo University of Technology

The flexible field emission (FE) cathode materials, with the unique deformability and bendability, have widely potential application in the fields of electronic textiles, distributed sensors, paper displays, and micro x-ray tubes. The grand challenge to push forward their applications is how to reduce the turn-on fields with enhanced electron emission stabilities. In the present work, aimed to the exploration of novel SiC flexible field emitters with totally high performances based on the local field enhancement effect and tailoring the electron state density near the Fermi level by doping strategy, SiC low-dimensional materials were synthesized via pyrolysis of polymeric precursor on the carbon fabric substrate. The morphology and doping levels of SiC nanostructures with enhanced FE properties were accomplished by optimizing the cooling rates and pyrolysis atmospheres. The turn-on fields of obtained SiC flexible FE cathodes could be to 0.98~1.90 Vμm-1 with the electron emission fluctuations of 7.7~14.1% under different temperatures and bending states, suggesting the explored SiC FE cathodes with high flexibility, low turn-on fields and high field electron emission stabilities. Keywords: polymeric precursor; pyrolysis; SiC low-dimensional nanostructures; flexibility; field emission

L-35 Synthesis, Self-Assembly, and Applications of Nanomaterials

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Qiao Zhang, Lei Chen, Yong Xu, Huicheng Hu, Muhan Cao Soochow University

Over the past decades, nanomaterials have attracted much attention due to their fascinating properties and versatile potential applications. In this presentation, I will summarize my recent efforts in the synthesis, stabilization and application of functional nanomaterials. In the synthesis part, by using gold nanoplates as a model system, we attempt to outline the key components that determine the formation of nanomaterials, clarify the roles of each reagent, provide highly reproducible recipes for synthesis, and therefore take a significant step towards the complete understanding of the mechanism behind the experimental phenomena. For the self-assembly, we constructured a metal-silica Janus nanostructures. Upon the addition of ethanol, the Janus nanostructures can form dimer or trimers immerdiately, which can be break up upon the addition of excess CTAB solution. For the catalytic application, we focus on the synergetic effect between metal facet and support facet. Keywords: Synthesis, self-assembly, Catalysis, Nanomaterials

L-36 Atomic layer deposition of functional nanomembranes as anode materials for lithium ion batteries Gaoshan Huang, Yuting Zhao, Yalan Li, Yongfeng Mei 2Department of Materials Science, Fudan University, Shanghai 200433, People’s Republic of China

Intensive exploration have been focused on discovering potential materials and fabrication techniques for superior safe and stable lithium ion batteries because of the increasing importance of battery technology as an environmentally benign power source. Here, we have synthesized 2D functional nanomembranes via atomic layer deposition (ALD) using sponge template. In the process of ALD on sponge, a uniform film was coated on all exposed framework, and was then disrupted into numerous pieces of nanomembranes when crushing the porous structure after removal of the sponge by annealing. This ALD-based strategy provides remarkable advantages: (1) precise control of thickness by simply changing deposition cycles; (2) high throughputs and yields considering excellent available surface area of the template; (3) cost efficiency by using commercial sponge with practical price; (4) ability of synthesizing various functional materials. TiO2 and ZnO nanomembranes synthesized by this approach exhibits good performance (high reversible capacity and superior cyclability) as anode materials of lithium ion batteries. No degradation was observed after 80 discharge/charge cycles at various current densities and following 500 cycles at 1 C. We noticed that the nanomembranes thickness showed significant influence on both bulk and capacitive capacities. Detailed voltammetric analyses were conducted to reveal the mechanism. Precisely controllable synthesis in this approach can flexibly adjust both bulk and surface Li storage and thus has important application potential. Keywords: atomic layer deposition; nanomembrane; anode; lithium ion battery

L-37 Bioinspired Graphene-Based Nanocomposites and Their Applications in Flexible Devices Qunfeng Cheng Beihang University

Graphene is the strongest and stiffest material ever identified and the best electrical conductor known to date, making it an ideal candidate for constructing nanocomposites used in flexible energy devices. However, it remains a great challenge to assemble graphene nanosheets into macro-sized high performance nanocomposites in

21 practical applications of flexible energy devices using traditional approaches. Nacre, the gold standard for biomimicry, provides an excellent example and guidelines for assembling two-dimensional nanosheets into high performance nanocomposites. In this review, we will summarize recent research on the bioinspired graphene-based nanocomposites (BGBNs), and discuss different bioinspired assembly strategies for constructing integrated high strength and toughness graphene-based nanocomposites through various synergistic effects. We will also highlight the fundamental properties of graphene-based nanocomposites,1-5 such as strength, toughness, and electrical conductivities. We will then move on to applications of the BGBNs in flexible energy devices, as well as potential challenges. Finally, we will attempt to spark aninspiration from the past work done by the community and depict a roadmap for the future of the BGBNs in flexible energy device applications. Keywords: Bioinspired, Graphene, Nanocomposites, flexible devices

L-38 Three dimensional nanostructured transition metal oxides based on porous conductive substrates for energy conversion and storage Lihua Qian, Chao Zhang, Xianglong Lv School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China

Transitional metal oxides exhibit potential applications for energy conversion and storage because of the reversible surface redox reactions. Particularly, the first-row transition metal (Fe, Co, Ni, and Mn) compounds have been considered as promising electrode materials for supercapacitor, metal-air batteries, water splitting devices, and fuel cells. However, limited by the poor kinetics during the redox reactions as a result of their low electrical conductivity and low surface area, nanostructured electrodes should be designed to significantly improve the electrochemical properties. As a result, owing to the tunable sizes and morphologies of nanoporous metal, nanostructured transition metal oxides grown on the conductive substrates have been considered as a very effective approach to improve the electrochemical activity. With high electrical conductivity and accessible surface area, the fabricated electrode can enhance charge transfer between electrode/electrolyte interfaces in favor of minimizing the internal resistance and mass transportation within the porous channels. Therefore, high performance energy storage device is usually assessed by high specific surface area and good electrical conductivity. We believe that the unique hybrid structure is very promising as advanced electrochemical electrode material for potential applications in diverse electrochemical energy storage and conversion devices. Keywords: Transition metal oxides; Nanoporous metal; Energy conversion and storage

L-39 Tribological Properties and Lubricating Mechanism of SiO2 Nano-particles in Water-based Fluid yueyue bao, jianlin sun, linghui kong School of Materials Science and Engineering, University of Science and Technology Beijing

In this paper, the friction properties of surface modified SiO2 nano-particles suspension in water-based lubricant have beenstudied.SiO2 (30nm) nano-particle was dispersed for surface modification with polyethylene glycol-200.Transmission electron microscope(TEM) and infrared(IR) spectroscopy show that SiO2 nano-particles disperse well and stably in the water-based lubricant. The diameter of the nano-particles is about 60 nm. Tribological properties of the water-based lubricant were evaluated using four-ball machine and pin-on-disk tester under different loads and different concentrations of SiO2 nano-particles. Worn surface morphology and element chemistry configuration of steel ball and steel ring were analyzed by means of X-ray photoelectron

22 spectroscopy (XPS) and scanning electron microscopy (SEM). Results show that the tribological properties of the water-based fluid have been improved by adding the nano-particles range from 0.1% to 0.3% concentrations. SiO2 Nano- particles deposited on to the wear track during the sliding, which helped to reduce the friction coefficient and increase the anti-wear properties due to the miniature ball bearing effect and self-repairing performance of nanoparticles between the friction pair. But with the increase of the load, the friction coefficient rises because of the abrasive wear of the SiO2 Nano- particles. Keywords: SiO2 nanoparticles , tribological properties , lubrication mechanism, abrasive wear

L-40 Influence of parameters on microstructures of composite coating fabricated by laser cladding YSZ@Ni core-shell nanoparticles Li Wang, Haizhong Zheng, Guifa Li, Xiaoyong Shu, Lingling Xiong School of Material Science and Engineering, Nanchang Hangkong University

YSZ@Ni core-shell nanoparticles were used to prepare composite coatings on the surface of Ni-based substrate by laser cladding. Nano-YSZ and YSZ/Ni mixing powders were also used for preparing composite coatings. The influences of laser beam velocity, laser power and powder bed depth on the coating microstructure were investigated in detail. Combined with the analyses of microhardness, the formation mechanism of the coatings obtained at different laser parameters was investigated. Results indicated that the composite coatings prepared by laser cladding YSZ@Ni core-shell nanoparticles on Ni-based alloy were better in the combination with the substrate than those prepared by laser cladding nano-YSZ and YSZ/Ni mixing powders. According to the effect of the four laser parameters on cladding quality, the powder type had the largest dependency, followed by laser beam velocity, and then the laser power. The powder bed depth had minimal impact. Keywords: YSZ@Ni core-shell nanoparticles; Composite coating; Microstructure; Laser cladding; Parameters

L-41 Fabrication of an inverse gradient nanostructure on an austenitic stainless steel by electro-magnetic induction heat treatment (EMIH) Tiehui Fang, Guoqing Huang College of materials science and engineering, Hunan University

An inverse gradient nanostructure (IGNS) has been fabricated on an austenitic stainless steel by using electro-magnetic induction heat (EMIH) treatment, in which the grain size changes from micrometer scale in the out surface to nanoscale in the inner center. Results show that the grain size gradient and volume fraction of the IGNS could be easily adjusted either by the input power or the treatment duration. Samples with various grain size gradients have been synthesized by different combinations of the parameters and subjected to tensile. Tensile results show that the mechanical properties of the IGNS samples both are affected by the grain size gradient and volume fraction. The optimum grain size distribution of the IGNS has been revealed and the underlying mechanisms are discussed. Keywords: Inverse gradient nanostructure; Electro-magnetic induction heat treatment (EMIH); grain size gradient; austenitic stainless steel;

L-42 Tribological Performances of Multilayer-MoS2 Nanoparticles in Water-based Lubricants

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Boming Zhang, Jianlin Sun School of materials science and engineering, University of Science and Technology Beijing this paper multilayer-2H-MoS2 nanoparticles were dispersed in water-based lubricants by a convenient and economically way. Oleic acid and triethanolamine were used as the main surfactants in the solution. Tribological performances of this lubricants were tested under high pressure and high rotating speed. FEI Tecnai G20 TEM, Malvern Zetasizer Nano ZS were used to test the particle size and Zeta potential. Tribological performances of this water-system with multilayer-MoS2 nanoparticles and the 3D-surface of wear scars after the tests were analyzed by means of four-ball friction wear testing machine and Olympus laser confocal microscope. According to Hertz theory and experimental data, it has practical significance to combine MoS2 nanoparticles with water-based Lubricants. Under high loading and high rotating speed the mixed suspension preforms good lubricating effects. The friction coefficient is 0.064 under 991N. When the rotating speed is 1800r/min the friction coefficient is 0.068. The binding energy of layers in MoS2 nanoparticles is less than the energy of shearing in friction pairs after calculation. The layers in MoS2 nanoparticles slide in the process of friction. It preforms the best lubrication effects when the friction process lasts about 500s. Keywords: Water-base lubricants；Multilayer -MoS2 Nanoparticles；Four-ball tribological test

L-43 Syntheses of nanoporous gold as high activity methanol / H2O2 catalyst by adjusting the circumferential speeds of Al-Au ribbon precursors Hui Xu Shandong University

We have prepared the nano-porous gold (np-Au) with a three dimensional (3D) bicontinuous interpenetrating ligament-channel structure by dealloying the melt spun Al2Au ribbon precursors with three different circumferential speeds (Sc). With increasing Sc, the lattice constant (a0) of precursors decreases and their cracking tendency increases, indicating an increase of compressive stress in the ribbons. After the dealloying procedure, the np-Au samples have an increasing a0 and a decreasing pore size with increasing Sc. There exists the heredity of the preferred orientation factors (F) between precursors and np-Au samples. The cyclic voltammetry (CV) curves of methanol electro-oxidation reaction (MOR) on np-Au samples are related to their F and show a higher activity with a higher Sc. In addition, np-Au with a lower pore size exhibit a higher sensitivity for the concentration of H2O2 in phosphate buffered solutions (PBS), which reaches 464.0 μA mM-1cm-2 with Sc = 18.3 m/s. These results suggest that we can change the pore size of the dealloyed np-Au by adjusting the Sc of the precursors, and then enhance the catalytic activity of np-Au. Keywords: dealloying;nanoporous gold; catalyst; methanol

L-44 Microstructural Characterization of Energy-related Low-dimensional Materials Jianbo Wang, He Zheng, Shuangfeng Jia, Huihui Liu, Cong Guo, Yi Xiong, Zhongling Xu School of Physics and Technology, Center for Electron Microscopy, MOE Key Laboratory of Artificial Micro- and Nano-structures, and Institute for Advanced Studies, Wuhan University, Wuhan 430072, China

Energy-related low-dimensional materials which can be potentially applied in electronic devices, optical devices, and rechargeable lithium/sodium batteries have attracted extensive attentions. However, full realization of their

24 applications in future devices requires a comprehensive understanding of their structure, which is yet to be explored. By employing the transmission electron microscopy (TEM), we have successfully revealed the complex structures in several energy-related materials: (1) The powdered crystalline samples of nominal composition Li1.07Mn1.93O4δ have been investigated by TEM combined with X-ray powder diffraction (XRD) at room temperature. As suggested by the TEM observation, the dominant phase of the particles is a cubic spinel Li1+αMn2αO4δ with space group . A monoclinic Li2MnO3 phase with C2/m space group was also identified. Furthermore, the occurrence of nanoscale rotational twinning domains in Li2MnO3 with 120° rotation angles, stacked along the [103]m/[111]c (“m” and “c” represent the monoclinic and cubic descriptions, respectively) axis was also observed. These nanoscale rotational twining domains are responsible for the pseudo-3-fold axis and their formation is supported by the superstructure reflections in selected-area electron-diffraction (SAED) patterns. Similar patterns were reported in the literature but may have been misinterpreted without the consideration of such domains. Consistent with the TEM observation, the XRD results reveal the increasing percentage of monoclinic Li2MnO3 with increasing annealing time, associated with more oxygen vacancies. In addition, the electron beam irradiation during TEM studies may cause the nucleation of nanoscale cubic spinel Li-Mn--O crystallites on the monoclinic Li2MnO3 grains. These results provide the detailed structural information about the Li1.07Mn1.93O4δ samples and advance the understanding of corresponding electrochemical properties of this material as well as other layer structured cathode materials for lithium-ion batteries. (2) Non-stoichiometric hexagonal-based KxWO3 nanosheets were synthesized by oxidizing tungsten foil in potassium hydroxide. The detailed electron microscopy and XRD investigations imply that the nanosheets were obtained by self-assembly of individual nanowires with monoclinic superstructures. Assisted by the group theory analysis, the parallel-aligned nanowires can be referred to as the 120o rotation domain variants in the superstructure phase, which may result from the rotation symmetry reduction induced by the ordered arrangements of K vacancies during crystal growth. Relying on this model, the kinematic simulations of the composite patterns agree well with the corresponding serial experimental diffraction patterns obtained by tilting the nanosheet. (3) A powder of oxyfluorotitanate Na3TiOF5 crystals is acquired as an intermediate product during the synthesis of anatase TiO2 nanosheets with a large percentage of exposed reactive {001} facets. By application of TEM techniques, mainly energy dispersive spectroscopy and selected-area electron diffraction, coherent domain variants of Na3TiOF5 are shown to possess monoclinic structure with space group P21/n. The occurrence of these orientation domain variants is attributed to the reduction of crystal symmetry as a result of the phase transition from the high temperature cubic phase to the low-temperature monoclinic phase. Through a detailed group theory analysis, the orientation domains are shown to exhibit 12 variants and 11 domain boundaries, which can be categorized into three types of perpendicular twins and two types of antiparallel twins. This work may provide meaningful insight for understanding the growth mechanism of anatase TiO2 with a high percentage of reactive facets. (4) TEM analysis revealed the co-existence of 12 possible TiOx monoclinic domain variants, which are induced by the cubic-to-monoclinic phase transition attributed to the Ti and O vacancy ordering. These 12 monoclinic domain variants which are predicted by group theory might be randomly arranged. Furthermore, several hours of electron beam irradiation can lead to the vacancy ordering–disordering transition (i.e. monoclinic-to-cubic phase transformation) in TiOx. Our results shed light on the structural characteristics in TiOx nanostructures and thus contribute to the fabrication and design of the related nanostructures. In addition, to investigate the energy-related materials’ behaviors under the working conditions, a nano-sized sodium ion battery was successfully built inside the TEM. Real-time microstructural evolution during the

25 sodiation of CuO nanowires (NWs) was directly recorded by in-situ TEM. It was found that the sodiation length was consistently proportional to the square root of the reaction time, indicating that the sodiation procedure was controlled by a long-range diffusion transport mechanism. Based on the sodiated products, the sodiation process was shown to consist of three steps. Cu2O and Na2O were predominantly formed during the first step, then, on further reaction, the intermediate NaCuO phase nucleated. The final sodiation products were Na6Cu2O6, Na2O and Cu. In contrast, no NaCuO nor Na6Cu2O6 phase was found during the previous ex situ electrochemical study. It is believed that because both NaCuO and Na6Cu2O6 phases are not stable in air ambient, they could not easily be detected during the ex situ experiment. Also, such discrepancy may originate from the different cell configurations used. Further studies are required in view of understanding the complicated reaction mechanisms and thus the capacity fading and structure disintegration for metal oxide electrode materials. Keywords: Low-dimensional Materials; Electrode Materials; Domain Structures

L-45 Theranostic medicine based on the fluorescent carbon dots Zaicheng Sun Beijing University of Technology

Carbon dots, as a rising fluorescent materials have attracted continuously attention for potential applications in LED, solar cells, sensor, bioimaging and photocatalyst. However, its photo luminescent quantum yield (PL QY) is still quite low, especially emission in long wavelength region like red light. Herein, we proposed increasing the PL QY by doped carbon dots with N or S, N. The PL QY of carbon dots dramatically rises up after doping with N. It can reach over 90%. The carbon dots prepared via bottom-up route show excitation independent emission. In order to extend the absorption in the visible light region, S element is further introduced into the carbon dots to form S, N co-doped carbon dots. Due to the introduction of S and N, there is another S state was introduced into the band gap. That results in the new emission at red light region. Blue, green and red light emissions were obtained from carbon dots. Due to the excellent biocompatibility and low cytotoxicity, we further conjugated the cisplatin with carbon dots to obtain the theranostic agent. We explored to adding more function onto the carbon dots, like self-targeting and therapeutic function to construct the integrating with targeting, bio-imaing and therapy function together. Keywords: carbon dots, fluorescent, theranostics, bioimaging

L-46 Carbon Materials for Wearable Electronics Yingying Zhang Tsinghua University

The development of flexible electronics and equipment attracts significant interests in recent years. Low-dimensional carbon materials are one kind of ideal materials for flexible electronics. It is of great importance to explore low cost and scalable preparation approaches for high performance flexible carbon materials-based wearable electronics. In this talk, our recent progress in developing high performance flexible electronics based on novel carbon fabric and nanocarbons will be discussed. For example, we demonstrated that carbonized silk fabric with a plain-weave structure, based on its unique N-doped graphitic carbon nanostructure and the macroscale woven structure, could be worked as strain sensors with both of high sensitivity (gauge factor of 9.6 in the strain range of 0%-250% and

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37.5 in the range of 250%-500%) and high tolerable strain (more than 500%). Besides, the as-obtained sensors have fast response (10,000 cycles). It was demonstrated that such strain sensors could be used for monitoring both of vigorous human motions (such as jumping, marching, jogging, bending and rotation of joints), subtle human motions (such as pulse, facial expression, respiration and phonation) and even sound, and further demonstrated the capture and reconstruction of human body movements with our sensors, showing their superior performance and tremendous potential applications in wearable electronics and intelligent robots. The concept could be readily extended to other fabrics, such as cotton, modal, wool fabrics and other artificial or natural fiber fabrics, paving a new way for the low cost and large scale fabrication of wearable strain sensors with superior performance. Our strategy provides new approaches for the low-cost and high performance production of flexible electronics, promising its high potential for practical applications. Besides, we will also present our recent work on the application of carbon nanotubes, graphene and their composites in flexible electronics. Keywords: carbon fabric, nanocarbon, flexible electronics, sensors, supercapacitors

L-47 Improving the Hydrogen Production in Water Splitting by a Simple Hot-press Process and Spontaneous Spatial Charge Separation Effect Wei-Hsuan Hung, Chien-Jung Peng, Kun-Lin Yang, Chin-Ru Yang Feng Chia University

The energy crisis is gradually serious at this generation. How to decrease the environmental impact from petrochemical fuel has been a main issue of the world focus. Therefore, many researchers develop alternative source as a key research objectives. Hydrogen energy is clean, high energy and renewable, and can be prepared from just water. As the carbon dioxide problem of fuel made, the hydrogen energy receive more and more attention and enhance its standing in energy. Photocatalytic water splitting is being investigated to produce hydrogen fuel, which produces H2 and O2 only, playing a significant role in renewable hydrogen energy. As a popular material,TiO2 photoelectrode has many advantages, but there is a serious limitation for example, it can only absorb ultraviolet light due to its wide band gap (3.2 eV). Besides TiO2, hematite (alpha-Fe2O3) thin films in photocatalysis water splitting is attracting considerable attention due to its extraordinary chemical stability in oxidative environment, low cost, nontoxicity, high resistance to corrosion, and favorable optical band gap (2.2 eV). With the strong visible light absorption, it can efficiently make use of the light less than 550 nm, which accounts for 30% of the total sunlight. However, the photcatalyst activity of hematite is limited by several key factors such as relatively poor absorptivity, very short excited-state lifetime (～10-12 s), poor oxygen evolution reaction kinetics, and a short hole diffusion length (2-4 nm). To address the limitation and improve solar conversion efficiency, enormous efforts have been focused on the development of hematite nanostructures and the modification of their electronic structure via elemental doping. Hematite nanostructures with an increased specific surface area and reduced diffusion length for minority carriers are expected to be more efficient in charge carrier collection. The intrinsic charge spatial distribution has to be taken into account when selecting the facets, as it results in accumulation of photoexcited electrons and holes on certain semiconductor facets. A practical strategy is proposed to facilitate the migration of holes in semiconductor by taking advantage of the Schottky barrier between semiconductor and metal. A high work function is found to serve as an important selection rule for building such desirable Schottky junction between semiconductor surface facets and metal. Besides the increase of surface area or the shape control, noble metal nanoparticle like copper, silver and gold has

27 attracting much attention because they can additionally absorb the visible and infrared light due to their extraordinary surface plasmon resonance (SPR) properties. A strong field, from the collective oscillations of surface electrons, can effectively inhibit charge recombination, and the plasmon-excited hot electrons from the plasmon decay can be transferred to the conduction band of adjacent semiconductor. The plasmonic noble metal has been integrated for enhancing the absorption with visible light spectrum. Without the general water splitting enhanced process, here, we develop a new technology of using a simple hot press process to improve carrier transport, charge separation and longtime stability for photocatalytic water splitting. We adopted TiO2-Fe2O3 cocatalyst as our photoanode, TiO2-Fe2O3 cocatalyst possess a wide-range photon absorption; ultraviolet and visible photons in the solar spectrum can be effectively absorbed by TiO2 and Fe2O3 due to the appropriate energy band gaps of these two metal oxide semiconductors. Furthermore, the heterogeneous interfaces of TiO2-Fe2O3 created strong build-in electric fields, which suppress the recombination of photo-generated electron-hole pairs. After the fabrication of the TiO2-Fe2O3 photoeletrode, we will precede the hot press procedure. In addition, plasmonic gold nanoparticles were incorporated into this two system, which would provide the strong field and hot electrons, resulting in the enhancement of visible light absorption efficiency and inhibit charge recombination, this leads the photocatalytic water splitting to achieve a further stage. The goal of making versatile photoelectrode is to effectively produce hydrogen from simple water splitting under. This study has successfully achieved the synthesis Au/pseudocubic Fe2O3 nanocomposite and hot pressed Au/TiO2-Fe2O3 photoelectrode for enhanced photoelectric responses under visible and AM1.5 light irradiation. In our design, the combination of pseudocubic Fe2O3 and plasmonic gold layer constituted a perfect resonance circumstance for the internal light absorption from taking advantage of the plasmon resonance effects and the formation of Schottky junctions. Moreover, the Au/TiO2-Fe2O3 photoelectrode improve the efficiency with a simple hot pressing process successfully decreasing of film and increasing of internal stress and surface plasmon resonance enhanced light absorption and photo-generated electron-hole pairs of electrical separation rate . Keywords: Water Splitting; Charge Spatial Separation; Hematite; H2 production; Hot-press

L-48 The functionalized graphene and MoS2 for the applications on supercapacitors and hydrogen generation Ching Yuan Su National Central University

In this study, we investigate the synthesis of functionalizied 2D materials,mainly based on graphene and nano-structured MoS2, as hybridized electrodes for energy devices such as supercapacitors and hydrogeneration catalyst. As for the graphene-based supercapacitors, we report a binder-free supercapacitor including a unique graphene electrode of hierarchical porosity composed of the submicrometer porosity ( 20 um) of 3D graphene self-assembled by nanopores ( 2.5 nm) of graphene flakes. We found that this unique graphene electrode, when used in a supercapacitor, shows improved performance include high specific capacitance ( 442 F/g ), fast rate charging/discharging, and excellent cycle stability (95% after 1600 cycle numbers), which were due to the creation of a high specific surface area and a diffusion path, thus promoting ion transport capability. Another topic, we report a facile approach to prepare dense arrays of MoS2 nanoribbons on conducting glass substrate(FTO). The degree of crystallinity of the as-prepared MoS2 was founded to be adjustable by varying the temperature through postannealing. We founded that the postannealing temperature at 170 °C result in a unique nanocrystalline MoSx structure (x ≈ 2.5), where the abundant and exposed edge sites by this method shows superior electrocatalytic efficiency (an overpotential of ∼211 mV at 10 mA/cm2 and a Tafel slope of 43 mV/dec) in the

28 hydrogen evolution reaction (HER) when compared to the thin-film MoS2. The report introduces a new concept for rapidly fabricating cost-effective and high-density MoS2/MoSx nanostructures on versatile substrates, which may pave the way for potential applications in frontier energy materials. Keywords: Graphene, supercapacitors, MoS2, Nanoribbons, hydrogen evolution reaction (HER)

L-49 The synthesis of different dimensional MoS2 structures and their enhanced hydrogen evolution reaction performance Bin Xiang, Lei Yang Department of Materials Science & Engineering, CAS key Lab of Materials for Energy Conversion, Synergetic Innovation Center of Quantum Information & Quantum Physics

Platinum and other noble metal have been recognized as the best catalysts for electrocatalytic hydrogen evolution reaction (HER).1,2 However, the high cost and limited resources of noble metals hinder their mass scale application. Transition metal dichalcogenides semiconductors are an exciting family member of catalysts for HER due to their earth abundance and low cost.3,4 Theory calculations and experimental studies have confirmed that the electrocatalytic activities of MoS2 mainly come from its edges, where the basal plane is chemically inert.5,6 Great efforts have been dedicated to improve the electrocatalytic activities by highly exposing the active edge sites of MoS2.7,8 In this work, we demonstrate different dimensional MoS2 structure synthesis and their enhanced hydrogen evolution reaction performance. Using a chemical vapor deposition method, we successfully synthesized one-dimensional (1D), two dimensional (2D) and three dimensional (3D) MoS2 structures. The transmission electron microscopy (TEM) , energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were utilized to characterize the structure and chemical composition of the as-grown MoS2. To evaluate the electrochemical activities of as-synthesized MoS2 structures, we carried out a HER in 0.5 M H2SO4 solution by a standard three-electrode electrochemical system. MoS2 structures were transferred to a glass carbon electrode (GCE). Ag/AgCl electrode (3M KCl) and graphite rod were served as the reference electrode and the counter electrode, respectively. All of the potentials were calibrated by a reversible hydrogen electrode (RHE). The polarization curve of blank GCE assures a negligible background activity for hydrogen evolution. The different dimensional structures exhibit various electrocatalytic performance during HER. We attributed it to different number of active sites exposed to the surface in the different structures. References (1) J. K. Norskov, C. H. Christensen, Toward efficient hydrogen production at surfaces, Science 312 (2006) 1322-1323. (2) J. Greeley, T. F. Jaramillo, J. Bonde, I. Chorkendorff, J. K. Nrskov, Computational high-throughput screening of electrocatalytic materials for hydrogen evolution, Nat. Mater. 5 (2006) 909-913. (3) D. Voiry, H. Yamaguchi, J. Li, R. Silva, D. C. B. Alves, T. Fujita, M. Chen, T. Asefa, V. B. Shenoy, G. Eda, M. Chhowalla, Enhanced catalytic activity in strained chemically exfoliated WS2 nanosheets for hydrogen evolution, Nat. Mater. 12 (2013) 850-855. (4) D. Voiry, M. Salehi, R. Silva, T. Fujita, M. Chen, T. Asefa, V. B. Shenoy, G. Eda, M. Chhowalla, Conducting MoS2 nanosheets as catalysts for hydrogen evolution reaction, Nano Lett. 13 (2013) 6222-6227. (5) B. Hinnemann, P. G. Moses, J. Bonde, K. P. Jrskov, Biomimetic hydrogen evolution: MoS2 nanoparticles as catalyst for hydrogen evolution, J. Am. Chem. Soc. 127 (2005) 5308-5309. (6) T. F. Jaramillo, K. P. Jrgensen, J. Bonde, J. H. Nielsen, S. Horch, I. Chorkendorff, Identification of active edge

29 sites for electrochemical H2 evolution from MoS2 nanocatalysts, Science 317 (2007) 100-102. (7) N. Zhang, S. Gan, T. Wu, W. Ma, D. Han, L. Niu, Growth Control of MoS2 Nanosheets on Carbon Cloth for Maximum Active edges exposed: an excellent hydrogen evolution 3D cathode, ACS Appl. Mater. Interfaces 7 (2015) 12193-12202. (8) Y. Li, H. Wang, L. Xie, Y. Liang, G. Hong, H. Dai, MoS2 nanoparticles grown on graphene: an advanced catalyst for the hydrogen evolution reaction, J. Am. Chem. Soc. 133 (2011) 7296-7299. Keywords: MoS2; CVD; Hydrogen evolution reaction

L-50 Controlled growth of Boron-based nanostructures and modulation of their physical properties Fei Liu, Haibo Gan, Luxi Peng, Xun Yang, Yan Tian, Jun Chen, Shaozhi Deng, Ningsheng Xu Sun Yat-sen University

Boron-based nanostructures have obtained considerable attention because they have fasnicating properties, such as low density, large modulus, high conductivity and low electron affinity. Although many efforts have been devoted to fabricating the boron-based nanostructures, the controlled synthesis of single crystalline boron-based nanostructures and modulation of their physical properties are still a big challenge for all the researchers. In our works [1-5], we envisaged a theramal boron reduction way to sucessfully synthesize the boron-based nanostructures under controll. Moreover, we systematically investigated the transportation, field emission and mechanical properties of the boron-based nanostructures. Based on our research, the base-up growth mode is more suitable for their nanodevice applications. Finally, we fabricated the boron-based nanodevices with nice work performances by modulating their growth mode, nanostructure density and morphology . References (1) Liu, F.; Tian, J. F.; Xu, N. S.; Gao, H. J. et al., Adv. Mater. 2008, 20, 2609. (2) Liu, F.; Su, Z. J.; Gao, H. J.; Xu, N. S. et al., Ad. Funct. Mater. 2010, 20, 1994. (3) Liu, F.; Gan, H. B.; Xu, N. S. et al., Small 2014, 4, 685. (4) Liu, F.; Tang, D M; Gan, H. B.; Xu, N. S. et al., ACS Nano 2013, 7, 10112. (5) Wang, X. B*.; Liu, F.*; Bando, Y.; Golberg, D et al., ACS Nano 2014, 8, 9801. Keywords: boron-based nanostructures, controlled synthesis, modulation, transportation properties, field emission

L-51 Strain hardening mechanism of 10 # steel by means of cold rolling qingshun cheng, xiaolei wu Institute of Mechanics，Chinese Academy of Sciences

Grain refinement can make conventional metal several times stronger, but lead to dramatic loss of ductility. However, Wu et al. promoted the strength and ductility of heterogeneous lamella (HL) structure in TI by asymmetric rolling deformation. So this paper attempts to research the strain hardening mechanism of HL-10 # steel produced by cold rolling, ultimately, achieves the combination: excellent strength and ductility. The experimental process includes constant strain rate tensile (CSRT), loading-unloading-reloading test (LURT), stress relaxation test (SRT). In tension, we found HL-10 # steel existed three deformational behavior: yield drop, transient and Lüders band. Moreover, according to LURT, it shows bauschinger effect in LURT cures. The result after analyzing the hysteresis loops reveals that back stress accounts for almost 52% of the flow stress, namely,

30 back stress hardening is the major hardening mechanism. In addition, characterizing the stress-relaxation behavior provides effective approach for probing the structural evolution of dislocations, as well as the activation volume. It indicates the mobile dislocation density increases but activation volumes reduce with the unloading strains increase. Meanwhile, the digital image correlation (DIC) represents the nephograms of local strain and strain rate for describing the macroscopic deformation process. It concludes that HL-10# steel contains soft and hard phases, hardening mechanism is not only forest dislocation hardening, but also back stress hardening, which gives rise to high strength and commendable ductility. Keywords: bauschinger effect, stress relaxation, back stress

L-52 Strength and ductility of Heterogeneous Lamella structured copper obtained by ECAP and heat treatment Zhihua Liu, Xiangde Bian, Xiaolei Wu State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences

The strengthening mechanism of the nano-composites was due to the dislocation strengthening and other strengthening mechanisms. As nano-crystalline (NC) materials have high yield strength with low ductility while coarse-grain (CG) materials have low yield strength but a high strain hardening rate. Therefore, how to combine the NC high strength and CG long uniform elongation is been researched by amount of work. There are kinds of strategies reported such as twin inducing plastics, precipitated phase hardening and phase transition inducing plastics, etc. Now a new strategy has been put forward, which is by producing a Heterogeneous Lamella structured (HL). The HL structure is characterized with soft micro-grained lamellae embedded in hard ultrafine- grained lamella matrix. The high strain hardening rate profit from both the dislocation hardening and back stress hardening developed from plastic incompatibility induced by microstructural heterogeneity. In the present work, pure copper was subjected to equal channel angular pressing (ECAP) with route A up to 2 passes and heat treatment in the subsequent step. Then a series of HL microstructure was obtained by different heat treatment temperature, which coming to a variety of degree of partial recrystallization. Followed by a series of mechanics performance testing such as microhardness test, quasi-tensile test, loading-unloading-reloading (LUR) test and stress-relaxation test, the mechanical properties and strain hardening ability as well as the dislocation hardening and back stress hardening behavior of this HL structure were brought to light. To make a deep analysis of the yield and hardening behavior, the Digital Image Correlation (DIC) test was performed. The experimental result shows that the HL2 (275℃×10min) and HL3 (285℃×10min) have a good matching of strength and ductility. Then strain hardening rate curves indicate that both HL2 and HL3 act with a continuous yielding behavior. LUR test conducted a quantitative characterization of the back stresses of each HL, among which an obvious Bauschinger effect was observed in HL2 and HL3. The value of back stress occupies nearly half of the flow stress. Otherwise, stress-relaxation test brings out one fact that dislocation hardening of HL2 decrease gradually with increscent strain, corresponding to decrease of mobile dislocation density. Thus, we draw a conclusion that back stress hardening and dislocation hardening act with a synergism. What’s more, the back stress hardening is the main souce of strain hardening ability of this HL material. Besides, the DIC test shows that the HL inhibits deformation localization and improve the strain hardening rate. Keywords: ECAP, heterogeneous lamella structure, strength and ductility, back stress hardening, dislocation hardening, copper

L-53

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Synthesis, Structure, and Optical Properties of Manganese Phthalocyanine Thin Films and Nanostructures Lu Meng1, Yuyan Han2, Kai Wang1, Pin Gao1, Chao Huang1, Yi Yao1, Wenhua Zhang1, Faqiang Xu1 1. University of Science and Technology of China 2. High Magnetic Field Laboratory, Chinese Academy of Sciences

Recently, metal phthalocyanines (MPcs) nanomaterials have attracted considerable attention, motivated by their unique optical and electronic properties and potential applications in light-emitting diode (OLED), organic field-effect transistor (OFET), solar cells, and optical waveguides.However, there are still great difficulties in controlling the morphology and crystalline quality and in modulating the optical property in solution, which is the most common synthesis route of MPcs nanomaterials. Herein, manganese phthalocyanine (MnPc) nanostructures (NS) with different morphologies are prepared on porous anodic alumina oxide (AAO) at different substrate temperature (Ts=50℃,80℃,110℃,140℃,170℃,200℃) in an organic molecular beam epitaxy (OMBE) system. The surface morphologies of the MnPc are studied using scanning electron microscopy (SEM) and the results show that the NS morphologies can be modulated by the control of Ts, as a result, the continuous films are obtained at 50℃ and 80℃ while the nanorods (NRs) , nanowires (NWs) are generated as Ts increases. At the same time, the lateral dimension of the NS decreases. The results of X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicate that the MnPc NS have excellent crystallinity. Additionally, the ultraviolet visible (UV–Vis) absorption spectra demonstrates that the main absorption bands of MnPc NS are much broaden than those of MnPc films. What's more, the NS broad absorption bands show slight blue-shift effect as Ts increases. The development of fabrication method of MPcs nanomaterials with controllable and excellent crystalline structures opens new possibilities for the applications of organic nanostructures. Keywords: MnPc nanostructure; OMBE;substrate temperature; optical property.

L-54 Enhanced electrocatalytic reduction of CO2 on Ag with increased unoccupied density of state Zhijiang Wang1, Jigang Zhou2, Yongfeng Hu2, Zhaohua Jiang1 1. MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China 2. Canadian Light Source Inc., Saskatoon, Saskatchewan S7N 0X4, Canada

Atmospheric concentration of carbon dioxide (CO2), a greenhouse gas, keeps rising due to the fossil fuel burning on an unprecedented scale. The atmospheric concentration of CO2 exceeds 400 ppm in the year 2015, which is ~50% higher than the level of interglacial periods. As a result, during the past 30 years, the global temperature risen ~0.2 °C per decade, which has damaged the marine ecosystems and terrestrial biosphere to a great extent. To develop scalable synthesis of carbon-containing fuels using CO2, H2O and renewable energy is an attractive alternative, which can close the anthropogenic carbon cycle. A key technological target for this goal is an efficient, robust and cost-effective CO2 electroreduction catalyst. In this report, we fabricated several Ag electrocatalysts and studied their CO2 electro-reduction properties compared to commercial Ag. Ag L-edge X-ray absorption near-edge spectroscopy was employed to characterize the electronic structure variation among the catalysts. It is found that increased unoccupied density of state (DOS) of d-characteristic of Ag endows the electrocatalyst with a higher selectivity and efficiency for CO2 reduction. The introduction of Ni into Ag matrix reduces unoccupied DOS of d-characteristic as the charge redistribution between Ag and Ni, worsening the active efficiency for CO

32 production. Density functional theory calculations were employed to understand the correlation of the unoccupied DOS with CO2 reduction activity, which confirm that increased unoccupied DOS makes catalyst surface have an optimized affinity to the intermediate COOH and CO, closer to the activity volcano, which facilitates CO formation. Nanoporous Ag electrocatalyst made by anodization-reduction processes the highest unoccupied DOS of d-characteristic among the samples, showing the best catalytic performance to reduce CO2 to CO. Meanwhile, its onset overpotential is 0.19 V and the highest Faradaic efficiency reaches 90%. The electrocatalyst stays at this level for 10 h without any noticeable activity change, possessing great potential to find applications in industry. Our understanding on structure-activity relationship may provide a guideline for designing high-performance CO2 reduction catalysts. Keywords: CO2 reduction; silver; catalytic performance; unoccupied density of state; structure-activity relationship

L-55 On the mesoporogen-free synthesis of single-crystalline hierarchically structured ZSM-5 zeolites in a dry gel system Tongguang Ge, Zile Hua, Xiaoyun He, Jianlin Shi Shanghai Institute of Ceramics，Chinese Academy of Sciences

Hierarchically structured zeolites (HSZs) have gained much academic and industrial interest owing to their multiscale pore structures and consequent excellent performances in varied chemical processes. Although a number of synthetic strategies have been developed in recent years, the scalable production of HSZs single crystals with penetrating and three-dimensionally (3-D) interconnected mesopore systems but without using a mesoscale template is still a great challenge. Herein, based on a steam-assisted crystallization (SAC) method, we report a facile and scalable strategy for the synthesis of single-crystalline ZSM-5 HSZs by using only a small amount of micropore-structure-directing agents (i.e., tetrapropylammonium hydroxide). The synthesized materials exhibited high crystallinity, a large specific surface area of 468 m2 g-1, and a pore volume of 0.43 cm3 g-1 without sacrificing the microporosity (0.11 cm3 g-1) in a product batch up to 11.7 g. Further, a kinetically controlled nucleation–growth mechanism is proposed for the successful synthesis of single-crystalline ZSM-5 HSZs with this novel process. As expected, compared with the conventional microporous ZSM-5 and amorphous mesoporous Al-MCM-41 counterparts, the synthesized HSZs exhibited significantly enhanced activity and stability and prolonged lifetime in model reactions, especially when bulky molecules were involved. Keywords: mesoporous materials • penetrating mesopores • scalable synthesis • single crystalline • zeolites

L-56 A Self-Powered and Stable Perovskite Based Photodetector–Solar Cell Nanosystem Wei Tian College of Physics, Optoelectronics and Energy, Soochow University

Light sensing in the ultraviolet (UV), visible, and near-infrared (NIR) range has a wide applications in many fields, such as industry, space exploration and national defense.[1] Hybrid organic–inorganic perovskites have attracted intensive interest as light absorbing materials in optoelectronic devices. To date, although great progress has been made in fabricating perovskite based photodetectors with high sensitivity and fast response speed, relatively little work has been focused on low-power, or even self-powered devices, which will hold great promise in future nanodevices or nanosystems operating independently, sustainably and wirelessly.

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In this work, we report a high-performance CH3NH3PbI3 film based photodetector, which exhibits broad response for wavelength ranging from UV to visible light, high responsivity and large on-off ratio. By depositing an ultrathin Al2O3 film on the perovskite surface as protection layer using atomic layer deposition (ALD) technique, we successfully enhance its long-term durability up to two weeks in air. Furthermore, we firstly report an integrated self-powered all-perovskite system for simultaneous energy conversion and light detection. The present integrated system can work effectively at a low voltage less than 1.0 V and does not require external power source, possessing good photoresponse and high reproducibility.[2, 3] We provide a promising route to construct high-performance portable devices aimed at reduced size and weight. References [1] W. Tian, H. Lu and L. Li, Nano Res. 2015, 8, 382-405. [2] H. Lu, Y.L. Ma, B.K. Gu, W. Tian and L. Li, J. Mater. Chem. A. 2015, 3, 16445-16452. [3] H. Lu, W. Tian, F. R. Cao, Y. L. Ma, B. Gu and L. Li, Adv. Funct. Mater. 2016, 26, 1296–1302. Keywords: Self-powered, Photodetector, Solar cell, Perovskite

L-57 Controllable Synthesis, Dual-mode Plasmon Coupling Enhanced Photothermal conversion and Cancer Treatment Application of Au@Cu2-xS Core/shell Nanocrystals with monocrystalline shell Muwei Ji，Jiatao Zhang Beijing Institute of Technology

In order to study the plasmon coupling and application of Au and Cu2-xS nanocrystals, Au@Cu2-xS core/shell nanocrystals were prepared by in-situ transforming non-epitaxial growth Au@CdS core/shell nanocrystals with Cu+ in toluene colloid. It was proven that the Cu2-xS shell of as-prepared Au@Cu2-xS nanocrystals was monocrystalline and Au core and Cu2-xS shell directly contacted by using such non-epitaxial growth and cation exchange reaction strategy. Based on the method, flexible sizes, morphologies and shell thickness of Au@Cu2-xS core/shell nanocrystals and their UV-vis-NIR spectrum could be exactly tailored. Due to the plasmon coupling of Au core and Cu2-xS shell, the absorption and photothermal conversion of Au@Cu2-xS core/shell nanorods in NIR region were enhanced. The photothermal conversion efficiencies of Au@Cu2-xS nanorods were up to 59.01% and 43.25% under irradiation of 808 nm laser (1 W/cm2) and 1064 nm laser(0.7 W/cm2) respectively. As photothermal therapy reagents, Au@Cu2-xS core/shell nanorods could kill the HeLa cells effectively under irradiation of 808 nm or 1064 nm laser. Keywords: Au@Cu2-xS core/shell nanocrystals, surface plasmon resonance coupling, photothermal, in vivo cancer treatment

L-59 (Invited) Atomically Engineered Nanomaterials and Operando NMR Spectroscopic Analysis for Energy Conversion and Storage Huagui Yang East China University of Science and Technology

Engineering efficient nanomaterials as catalysts has attracted intensive research efforts due to its potential for energy conversion and storage. Herein, we studied various atomically engineered catalytic nanomaterials for energy conversion and storage. First of all, using polymer ligands to control the size and valence state of platinum monoxide clusters, we found that Pt in a higher oxidation has remarkable hydrogen oxidation reaction suppression

34 ability, while its H2 evolution capacity is still comparable to that of the benchmark of conventional Pt cocatalyst through comprehensive experimental and theoretical analysis1. Then, we explored the active sites of Pt/TiO2 photocatalyst on atomic level by a collaborative analysis from both experimental and theoretical work; metallic Pt0 nanoparticles have little contribution to the activity of solar water splitting and by contrast, oxidized species Ptδ+ truly take the role of the catalytic active sites2. Moreover, we anchored isolated Pt atoms on TiO2 and this photocatalyst exhibits a high solar-driven hydrogen evolution performance compared with Pt nanoparticles or clusters. The configurations of the isolated Pt atoms and their catalytic hydrogen evolution activity were calculated by large-scale periodic DFT analysis3. Additionally, we found that the photoreactivity of hydrogen generation can be correlated with the cluster size of the oxidized platinum cocatalyst as function, and the maximum turnover frequency is found on the smallest-sized cocatalyst4. These findings may pave the way for developing other high-efficientcy platinum-based catalysts for energy conversion and storage. We also engineered other efficient nonplatinum-based nanomaterials for energy conversion and storage. First, we modulated the local atomic structure of a classical but inert transition metal oxide, WO3, to be an efficient electrocatalyst (WO2.9) for hydrogen evolution in acidic water, which has shown promise as an alternative to platinum. Structural analyses and theoretical calculations together indicate that the origin of the enhanced activity could be attributed to the tailored electronic structure by means of the local atomic structure modulations5. In addition, we synthesize a nickel–carbon-based catalyst, from carbonization of metal-organic frameworks, to replace currently best-known platinum-based materials for electrocatalytic hydrogen evolution. This nickel-carbon-based catalyst can be activated to obtain isolated nickel atoms on the graphitic carbon support when applying electrochemical potential, exhibiting highly efficient hydrogen evolution performance with high exchange current density of 1.2 mA cm-2 and impressive durability6. Then, we prepared an amorphous Zn-Ge-O with a built-in inorganic chromophore-like structure, which shows a dramatically expanded visible-light absorption range. Structural characterizations and theoretical calculations together reveal that the origin of visible-light response can be attributed to the unusual metallic Ge-Ge bonds which act in a similar way to organic chromophores7. Furthermore, we designed and synthesized a surface H-bonding network decorated g-C3N4 photocatalyst with high efficiency of visible-light-driven H2 production. According to NMR and theoretical modeling, the H-bonding bridge can effectively shorten the distance between water molecules and g-C3N4, provide multiple channels for the transition between protons and the excited electrons on g-C3N4, stabilize the anionic intermediate and transition states, and restrain charge recombination8. These findings illustrate the significance of atomic structure engineering and should pave the way for efficient solar conversion devices. Proton transfer process at solid-liquid interfaces is the key point deciding the energy conversion efficiency of water splitting reaction. Although a series of methodologies for mechanism study, such as STM, TPD and DFT have been used to address the central questions in HER, the vast majority of them usually operate under ideal conditions, and it is still a quite tough task to take into account the complexities of practical conditions such as solvent effect, surface specificity, and adsorbate-adsorbate interactions. Therefore, identifying proton transfer routes deep into the realistic heterogeneous photocatalytic process is one of the most important mission of scientific research accumulation in this field. Based on an operando nuclear magnetic resonance (NMR) method, we will aim to recognize the type of hydrogen compounds, track the reaction trajectories and quantitatively analyze the intermediates in a TiO2-based realistic photocatalytic hydrogen evolution model system. In this system, the effective protons for HER are mainly from H2O, and CH3OH evidently serves as an outstanding sacrificial agent reacting with holes. The result reveals the relationship among electronic structure and charge distribution of the photocatalysts, system parameters, holes transfer processes, protons reduced processes and hydrogen production9. It is of great theoretical and practical significances in guiding the design and preparation of efficient photocatalytic systems for energy conversion and storage.

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Keywords: Nanomaterials, Platinum-based catalysts, Nonplatinum-based catalysts, NMR Spectroscopic Analysis.

L-60 Thermal atomic layer deposition of TiO2 thin films- Analysis of affecting factors on growth repeatability Changwei Yang Jiaxing micro electronic instrument and equipment Engineering Center, Chinese Academy of Sciences

Atomic layer deposition (ALD) has been widely used in the preparations of metal oxides, metal nitrides and metal films due to its excellent 3D-shape conformity and precise nano-size control . However, during the ALD process, the changes of the process parameters always result in diffirent thickness and properties of the thin films. Therefore, it is necessary to find out the factors that influence the repeatability of each process. In this paper, the TiO2 thin films were preparated by thermal atomic layer deposition (TALD) with titanium tetrachloride (TiCl4) and H2O as the Ti and O precursors, and spectroscopic ellipsometry was used to measure the thickness of the samples. The results show that in order to obtain the same results many affecting factors, such as the device itself, the temperature of the chamber and precursors, the volume fraction of the precursor, the exposure time and the position of the substrate, can not be ignored. Keywords: atomic layer deposition; TALD; TiCl4; TiO2; repeatability

L-61 Thermoelectric enhancement in BiCuSeO via doping site tuning Yazhou Sun, Liangming Peng University of Science and Technology of China

Objective: BiCuSeO-based thermoelectric (TE) materials with intrinsically low thermal conductivity have attracted much attention. The effects of replacing Bi by Sb (dielectric layer doping) and substituting Te for Se (conductive layer doping) on TE performances of BiCuSeO are examined. Methods: BiCuSeO, Bi0.98Sb0.02CuSeO and BiCuSe0.975Te0.025O bulk specimens were prepared by a conventional two-step solid state reaction followed by induction hot-pressing. Stoichiometric powders of Bi2O3 (99.9%), Bi (99.9%), Cu (99.7%), Se (99.9%), Sb (99.99%) and Te (99.99%) were weighed. The initial powders were uniformly mixed and then sealed in evacuated silica tubes. The silica tubes were heated to 573 K within 12 h and then to 923 K within 9 h with heating and cooling rates of 5 K/min and 3 K/min, respectively. The obtained ingots were pulverized into powders and sieved by a 300 mesh sieve. The powders were densified into disk-shaped samples with dimensions of f 20 mm × 3.2 mm under an axial pressure of 180 MPa at 873 K for 12 min in argon atmosphere. Electrical conductivity (σ) and Seebeck coefficient (S) were measured between 300 and 750 K in a high purity helium atmosphere using an Ulvac-Riko ZEM-3 instrument system. The total thermal conductivity () was calculated usingand the related parameters were experimentally determined. Results: The XRD results show all the samples can be indexed to standard BiCuSeO (PDF#45-0296) as a major phase and a weak peak from remaining Bi2O3 is observed. All the samples exhibit positive S and their σ increases with rising temperature, indicating p-type semiconductor behavior. Overall, Sb doping decreases S, improves σ to a maximum value of 48.7 S/cm and causes increment in thermal conductivity for Bi0.98Sb0.02CuSeO. However, Te doping produces opposite effect. In particular, a prominently enhanced S as high as 342 μV/K at 750 K is achieved for BiCuSe0.975Te0.025O. As a result, both doping sites lead to a remarkable increment in the power factor (PF) and figure of merit (ZT) at 750 K for Bi0.98Sb0.02CuSeO and BiCuSe0.975Te0.025O. The highest values of PF～3.8 μW/cmK2 and ZT～0.56 are obtained for the former and latter oxyselenides,

36 respectively. The corresponding values for the pristine BiCuSeO are 2.54 μW/cmK2 and 0.39 umder the same condition. Conclusion: The TE performances of BiCuSeO are significantly enhanced via doping site tuning. The results provided a potential technical approach for optimizing TE properties of BiCuSeO oxyselenides. Keywords: BiCuSeO; thermoelectric; Seebeck coefficient; doping

L-62 Nanotechnology and the machines of the future Osvaldo Oliveira University of Sao Paulo

The combination of machine learning and Big Data methodology is revolutionizing science and technology, with the prospects of machines increasingly outperforming humans in intellectual tasks. Much of these developments depends on nanotech-based methods to produce devices and machines, as well as for acquiring data. In this lecture, I will use the example of computer-assisted diagnosis systems to illustrate the required merge of nanotechnology and Big Data in order to successfully build such systems. More specifically, I will address the use of nanomaterials in biosensors and other diagnosis devices, with particular emphasis on the fabrication of nanostructured films employed to detect cancer and tropical diseases. Of particular relevance is the continuous monitoring of health conditions, probably demanding wearable and implantable biosensors to be developed with nanotechnology. With some of these biosensors the data have to be treated with statistical and computational methods for a precise diagnosis to be made, which already points to the importance of data processing. For a full-fledged computer-aided diagnosis system, however, a considerably more sophisticated approach is required, with massive amounts of data from different sources being integrated seamlessly. It is clear that these stringent requirements can only be met with a paradigm shift involving the convergence of nanotechnology and Big Data. Keywords: nanostructured films, biosensors, Big Data

L-63 Role of point defects on the enhancement of NH3 gas sensing properties in ZnO nanostructures Sundara Venkatesh Perumalsamy, Jeganathan Kulandaivel Sri S. Ramasamy Naidu Memorial College，India，Bharathidasan University, India

NH3 gas sensing properties of ZnO nanostructures has been investigated under various temperatures. The morphological transitions occur from vertical standing nanorods to inclined and tapered nanostructures with increasing the argon sputtering pressure. The dominant green emission around at 2.28 eV in the photoluminescence spectra signifies the presence of oxygen vacancies in the ZnO nanostructures which increases as a function of argon sputtering pressure. For 25 ppm NH3 gas at room temperature, a response time of 49 sec and a fast recovery time of 19 sec are attributed to the modification in the intermediate defect states induced by the oxygen vacancies through the adsorption and desorption of gas molecules on the surface of ZnO nanostructures. Keywords: ZnO nanostructures, Sputtering, Raman Scattering, Point defects, NH3 gas sensor

L-64 Dewetting Mediated Assembly of Colloidal Microspheres on Patterned Substrate Weibin Li

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National Microgravity Laboratory, Institute of mechanics, CAS

Droplet evaporation occurs widely in nature all the time. The dewetting phenomenon always occurs in evaporation of a colloidal droplet on a solid substrate. In our previous studies, we found a two-dimensional network pattern inside the coffee ring, which is formed by dewetting of liquid film. The liquid film dewetting process, which mediated assembly of microspheres, is related to the wettability of the substrate. What attract us is how to control the microspheres assembly and form special patterns as our predictions. In fact, we could design patterned substrate by changing the wettability of the surface, and try to control the dewetting process of liquid film and deposition process of microspheres, and further to deposit microspheres into special patterns. Based on the above way of thinking, a hydrophilic substrate whose certain regions coated with a layer of hydrophobic membrane is prepared. The rupture of the liquid film initiates at the hydrophobic regions, then microspheres are pushed and aggregated in the hydrophilic region under the lateral capillary immersion force. The microspheres assembled into ordered structure in the hydrophilic regions, while the hydrophobic regions is still particle-free. We finally obtain a two-dimensional colloidal crystal with specific particle-free regions. This method may help us to regulate the location of the vacancy and distribution of microspheres in photonic crystal preparation.

Poster

L-P01 Preparation and performance research of nickel metal aerogel of high specific surface area Xiaocao Zhou Southwest University of Science and Technology

L-P02 Cracks formation in the vertical co-depositing colloidal crystal Honghui Sun, Ding Lan, Yuren Wang Chinese Academy of Sciences,Institute of Mechanics,National Micogravity Lab,Key Lab Microgravity

L-P03 Modulating the Phases of Iron Carbide Nanoparticles: From a Perspective of Interfering the Carbon Penetration of Fe@Fe3O4 by Selectively Absorbed Halide Ions Ziyu Yang, Xin Chu, Yanmin Ju, Yanglong Hou Peking University

L-P04 Multifunctional Fe@Au Nanoparticles for Cancer Theranostics Ren-Jei Chung National Taipei University of Technology (Taipei Tech)

L-P05 Self-assembly and metalation of optically active nanocrystals with enhanced photocatalytic performance Jiefei Wang, Yong Zhong, Feng Bai Key Laboratory for Special Functional Materials of the Ministry of Education, Henan University

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L-P06 Interfacial Self-Assembly Driven Formation of Hierarchically Structured Nanocrystals with Photocatalytic Activity Yong Zhong, Jiefei Wang, Feng Bai Key Laboratory for Special Functional Materials of the Ministry of Education, Henan University

L-P07 Artificial Chloroplasts: Conjugated Photo-/Photothermal Catalysis towards Reduction of CO2 to CH4 Jia Liu1,2, Tsubasa Imai1,3, Qingmin Ji1, Lok Kumar Shrestha1, Katsuhiko Ariga1, Hideki Abe1,3 1. World Premier International (WPI) Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, Ibaraki 305-0044, Japan 2. Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China 3. Environment and Energy Materials Division, National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, Ibaraki 305-0044, Japan

L-P08 Layer-controlled Pt-Ni porous nanobowls synthesized in water at room temperature Hongsheng Fan1, Ming Cheng1, Zhenlei Wang1, Rongming Wang2 1. Department of Physics, Beihang University, Beijing 100191, China 2. School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China

L-P09 Self-Supported Foam-Like Co3O4 Microspheres as High-Performance Pseudocapacitor Electrodes Ming Cheng1, Rongming Wang2 1. Department of Physics, Beihang University, Beijing 100191, P. R. China 2. School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, P. R. China

L-P10 Ultrahigh responsive humidity sensor from biomass waste xiluan wang Beijing Forestry University

L-P11 An abnormal phase transition behavior in VO2 nanoparticles induced by a M1-M2-R process: two anomalous high (> 68 °C) transition temperatures Bingrong Dong1, Yanfeng Gao1,2, Hongjie Luo1,2 1. Shanghai institute of Ceramics, Chinese Academy of Sciences 2. School of Materials Science and Engineering, Shanghai University

L-P12 Formation mechanism of Au-Cu bimetallic nanoclusters generated by plasma gas condensation Jiang-shan Luo1,2, Xi-bo Li1, Jiang-lei Huang2, Wei-dong Wu1, Yong-jian Tang1,2

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1. Research Center of Laser Fusion, Science and Technology on Plasma Physics Laboratory, China Academy of Engineering Physics, Mianyang, Sichuan, China 2. Laboratory for Matter Properties at Extreme Conditions, Southwest University of Science and Technology, Mianyang, Sichuan, China

L-P13 Studies on the Luminescence Properties of the Bluish-Green Persistent SrAl2O4: Eu2+,Dy3+ Phosphor by the Molten Salt Method AiYan Ji, YanFeng Gao Shanghai University

L-P14 Raspberry-like Hollow Carbon Nanospheres with Enhanced Matrix-free Peptide Detection Profiles Tingting Liu Curtin University

L-P15 Solid-state-reaction synthesis of VO2 nanoparticles with low phase transition temperature, enhanced chemical stability and excellent thermochromic properties Nan Shen1, Yanfeng Gao2 1. Shanghai Institute of Ceramics (SIC), Chinese Academy of Sciences (CAS) 2. Shanghai University

L-P16 Study of SnO2 thin film on aerogel by atomic layer deposition fan yang, xuan luo, ruizhuang yang, lin zhang Laser Fusion Research Center, China Academy of Engineering Physics

L-P17 Preparation and optical properties of Au nanoclusters by magnetron sputtering method Jianbo Zhang, Yali Wang, Jiangshan Luo, Xibo Li Science and Technology on Plasma Physics Laboratory, and Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621999, P. R. China.

L-P18 Fabrication of 2.9-Terahertz quantum cascade laser ZhiQiang Zhan Laser fusion research center, China Academy of Engineering Physics

L-P19 Thermal stability of Ti6Al4V nanocrystalline layer produced by surface mechanical attrition treatment quantong Yao Key Laboratory of Electromagnetic Processing of Materials, Ministry of Education, Northeastern University, Shenyang 110004 China

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L-P20 Single-step Synthesis and Thermal Stability of Larger Interplanar Spacing Nanocrystals Ti3C2 Aihu Feng1,2, Yun Yu1, Yong Wang1,2, Feng Jiang1,2, Yang Yu1, Le Mi1, Lixin Song1 1. Key Laboratory of Inorganic Coating Materials CAS, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, PR China 2. University of Chinese Academy of Sciences, Beijing 100049, PR China

L-P21 The Growth and Application of Dot-in-perovskite Nanowire Ruili Wang ShanghaiTech University, Shanghai, PR China

Publish Only

Enhancing dispersion of ultra-fine WC powders via chemical modification with physical means Lei Guo, Lairong Xiao, Xiaojun Zhao, Zhenyang Cai, Yufeng Song School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083, China

Uniform and dispersed ultra-fine WC powders were obtained using sodium dodecyl sulfate (SDS) with physical means. The influence of dispersion conditions on the powders dispersion was studied. The dispersion of WC powders was controlled by the amount of dispersant, dispersing time, solid-liquid ratio and dispersion time. The particle size and distribution on WC powders was tested by the laser particle size analyzer. The dispersed WC powders were characterized by X-ray diffraction, scanning electron microscope and energy-dispersive spectrometry. The results indicated that SDS was adsorbed and scattered on the WC powders, which could enhance the stability and dispersibility of suspension by the electrostatic effect. The diameter of dispersed WC powders ranged from 0.4 to 0.6μm. A corresponding dispersive mechanism was investigated. In this investigation, the optical dispersing time, solid-liquid ration and the concentration of SDS for the dispersed WC powders is 300min, 1:20 and 1.4g/L, respectively.

Size-dependent photoluminescent property of gold and YVO4:Eu3+ hybrid nanoparticles Wei Zhang, Yinglin Yan, Fengqi Guo, Lisheng Zhong, Yan Wang, Yunhua Xu Xi’an University of Technology

The nano sized gold particles with different grain sizes were successfully synthesized by a seeding growth method and then mixed with europium doped yttrium vanadate nanophosphors (YVO4:Eu), which were prepared via a hydrothermal method. The microstructure and luminescent properties were charaterized by X-ray diffraction (XRD), transmission electronmicroscopy (TEM), UV-Visible absorption spectrum(UV-Vis),and photoluminescence (PL) spectroscopy. The growth process of uniform spherical gold nanoparticles with four diameters was discussed. Moreover the effect of gold nanoparticles’ grain size on the luminescent properties of YVO4:Eu nanosphorsphors was studied in detail. All the fluorescence spectra of the mixtures still presented the characteristic red emission of Eu3+. It was interesting to observe that the emission intensity of YVO4:Eu nanosphorsphors was increasing with the growing of the gold nanoparticles. The improve mechanism was discussed as well.

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High performance two-ply carbon nanocomposite yarn supercapacitors enhanced with a platinum filament and in situ polymerized polyaniline nanowires qiufan Wang South-Central University for Nationalities

Two-ply yarn supercapacitors behave like conventional textile yarns to power next generation electronic textiles. To improve the capacitance of the yarn, we produced a metal filament reinforced carbon nanotube composite yarn which was further in-situ polymerized with polyaniline nanowires for use as electrodes. The wearable two-ply yarn supercapacitor made from the composite electrodes possesses very high capacitance (91.67 mF cm-2) and energy density (12.68 μWh cm-2), and excellent long term cycling stability for charging-discharging and flexing deformation. The two-ply nanocomposite yarn supercapacitors have been connected in series and in parallel to power miniature electronic devices on smart textiles.

Synthesis of HfB2 Nanoparticles Via an In-situ Molten-Salt-Mediated Magnesiothermic Reduction Shaolei Song1, Qiang Zhen1, Rong Li2 上海大学材料科学与工程学院 1, 上海大学纳米科学与技术研究中心 2

Hafnium diboride (HfB2) nanoparticles were successfully synthesized through an in-situ molten-salt-mediated magnesiothermic reduction. HfB2 precursor (HBP) can be obtained via a sol-gel route using Na2B4O7·10H2O and HfOCl2·8H2O as starting raw materials. With Hf/B/Mg mole ratio of 1:5:10. Phase transformation analysis and structural evaluation were carried out by means of fourier infrared spectrum (FTIR) and X-ray diffractometry. Morphology and microstructure were characterization scanning electron microscopy (SEM) and transmission electron microscope (TEM). The XRD results revealed that HfB2 can be formed at 750°C and HBP could be completely converted into pure HfB2 with average crystallite size of 24 nm after 4h at 1200 °C. After acid leaching process, SEM showed that the particle size of obtained HfB2 powders were around 50-60 nm and had favourable dispersibility. In addition, the formation of NaCl in the sol-gel process is believed to be responsible for the reduced synthesis temperature and good dispersion of final HfB2 product powders.

Synthesis and growth mechanism of curly silver nanowires with high catalytic activity for the reduction of p-nitrophenol Xianwei Meng, Hongwei Yang, Cangyi Hu, Yongyun Mao, Yuwen Yang, Hao Cui, Jialin Chen Kunming Institute of Precious Metals

In this work, We report a simple one-step synthesis method of the curly silver nanowires at room temperature without organic substance. Scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet-visible (UV-vis) spectroscopy were combined to characterize this bending and twisting silver nanowires and the possible growth mechanism of the products is proposed. The growth mechanism of curly AgNWs is divided into two steps: the first step is the synthesis of silver flakes with irregular shape; the second is AgBr helps reduce the concentration of free Ag+ in the solution and silver flakes is etched into curly AgNWs by O2/Brˉ/Fe(III). Furthermore, the catalytic activities of the obtained silver nanowires for the reduction of 4-nitrophenol (4-NP) with excess NaBH4 were tracked by UV-visible spectroscopy. The results revealed that the products exhibited high catalytic activity in the reduction of 4-NP. The simple preparation route and high catalytic performance make the materials highly promising candidates for diverse applications in the area of catalysis.

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Welded-Ag-nanowires/FTO conducting film with high transmittance and its application in transparent supercapacitors Zhensong Qiao, Xiaopeng Yang, Feng Liu, Guangbin Duan, Bingqiang Cao Materials Research Center for Energy and Photoelectrochemical Conversion, School of Material Science and Engineering, University of Jinan, Jinan 250022, Shandong, China.

Silver nanowires (AgNWs) are widely seen as the next-generation transparent conductive electrodes (TCEs) in optoelectronic and energy storage devices owing to its high optical transmittance and surface area, low sheet resistance, and facile processing. In the paper, AgNWs with a small diameter are synthesized by a facile and novel polyol reduction method. Ag nanowires ink is then spin coated onto F-doped SnO2 (FTO) to form the AgNW/FTO conducting film. Welding treatment of the AgNW/FTO conducting film not only decreases the sheet resistance from 11.4 ohm sq-1to 9.8 ohm sq-1 and increases the optical transmittance from 71.9 % to 79.3 % at 550 nm, but also improves the adhesivity of AgNW network on FTO substrate. Furthermore, MnO2 nanosheets are directly deposited on welded-AgNW/FTO (wAF) substrate to prepare a transparent MnO2/weled-AgNW/FTO (MwAF) composite electrode. The MwAF electrode displays excellent electrochemical performance, including high specific capacitance (375 F g-1 at 5 mV s-1) and superior cycle stability (173.3 % of the initial capacitance after 20000 GCD cycles).

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