Oxidation State Analyses of Uranium with Emphasis on Chemical Speciation in Geological Media
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Tuning Wettability of Molten Lithium Via a Chemical Strategy for Lithium Metal Anodes
ARTICLE https://doi.org/10.1038/s41467-019-12938-4 OPEN Tuning wettability of molten lithium via a chemical strategy for lithium metal anodes Shu-Hua Wang1, Junpei Yue1, Wei Dong1,2, Tong-Tong Zuo1,2, Jin-Yi Li1,2, Xiaolong Liu1, Xu-Dong Zhang1,2, Lin Liu1,2, Ji-Lei Shi 1,2, Ya-Xia Yin1,2 & Yu-Guo Guo 1,2* Metallic lithium affords the highest theoretical capacity and lowest electrochemical potential and is viewed as a leading contender as an anode for high-energy-density rechargeable 1234567890():,; batteries. However, the poor wettability of molten lithium does not allow it to spread across the surface of lithiophobic substrates, hindering the production and application of this anode. Here we report a general chemical strategy to overcome this dilemma by reacting molten lithium with functional organic coatings or elemental additives. The Gibbs formation energy and newly formed chemical bonds are found to be the governing factor for the wetting behavior. As a result of the improved wettability, a series of ultrathin lithium of 10–20 μm thick is obtained together with impressive electrochemical performance in lithium metal batteries. These findings provide an overall guide for tuning the wettability of molten lithium and offer an affordable strategy for the large-scale production of ultrathin lithium, and could be further extended to other alkali metals, such as sodium and potassium. 1 CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, CAS Research/Education Center for Excellence in Molecular Sciences, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences (CAS), 100190 Beijing, China. -
A Protein Engineered to Bind Uranyl Selectively and with Femtomolar Affinity
ARTICLES PUBLISHED ONLINE: 26 JANUARY 2014 | DOI: 10.1038/NCHEM.1856 A protein engineered to bind uranyl selectively and with femtomolar affinity Lu Zhou1†, Mike Bosscher1†, Changsheng Zhang2,3†,SalihO¨ zc¸ubukc¸u1, Liang Zhang1, Wen Zhang1, Charles J. Li1, Jianzhao Liu1, Mark P. Jensen4, Luhua Lai2,3* and Chuan He1* 21 ∼ Uranyl (UO2 ), the predominant aerobic form of uranium, is present in the ocean at a concentration of 3.2 parts per 109 (13.7 nM); however, the successful enrichment of uranyl from this vast resource has been limited by the high concentrations of metal ions of similar size and charge, which makes it difficult to design a binding motif that is selective for uranyl. Here we report the design and rational development of a uranyl-binding protein using a computational screening process in the initial search for potential uranyl-binding sites. The engineered protein is thermally stable and offers very high affinity and selectivity for uranyl with a Kd of 7.4 femtomolar (fM) and >10,000-fold selectivity over other metal ions. We also demonstrated that the uranyl-binding protein can repeatedly sequester 30–60% of the uranyl in synthetic sea water. The chemical strategy employed here may be applied to engineer other selective metal-binding proteins for biotechnology and remediation applications. ranium is the key element for nuclear-energy production and Through billions of years of evolution nature has produced is important in many other applications. The most stable and strategies to recognize beneficial or toxic metal ions with high Urelevant uranium ion in aerobic environments is the uranyl sensitivity and selectivity. -
Hierarchically-Structured Metalloprotein Composite
ARTICLE There are amendments to this paper https://doi.org/10.1038/s41467-020-14709-y OPEN Hierarchically-structured metalloprotein composite coatings biofabricated from co-existing condensed liquid phases ✉ Franziska Jehle 1, Elena Macías-Sánchez1, Sanja Sviben1, Peter Fratzl1, Luca Bertinetti 1 & ✉ Matthew J. Harrington 1,2 1234567890():,; Complex hierarchical structure governs emergent properties in biopolymeric materials; yet, the material processing involved remains poorly understood. Here, we investigated the multi- scale structure and composition of the mussel byssus cuticle before, during and after for- mation to gain insight into the processing of this hard, yet extensible metal cross-linked protein composite. Our findings reveal that the granular substructure crucial to the cuticle’s function as a wear-resistant coating of an extensible polymer fiber is pre-organized in con- densed liquid phase secretory vesicles. These are phase-separated into DOPA-rich proto- granules enveloped in a sulfur-rich proto-matrix which fuses during secretion, forming the sub-structure of the cuticle. Metal ions are added subsequently in a site-specific way, with iron contained in the sulfur-rich matrix and vanadium coordinated by DOPA-catechol in the granule. We posit that this hierarchical structure self-organizes via phase separation of specific amphiphilic proteins within secretory vesicles, resulting in a meso-scale structuring that governs cuticle function. 1 Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, -
X-Ray-Based Spectroscopic Techniques for Characterization of Polymer Nanocomposite Materials at a Molecular Level
polymers Review X-ray-Based Spectroscopic Techniques for Characterization of Polymer Nanocomposite Materials at a Molecular Level 1, 2,3, 1 4, 1, Dongwan Son y, Sangho Cho y , Jieun Nam , Hoik Lee * and Myungwoong Kim * 1 Department of Chemistry and Chemical Engineering, Inha University, Incheon 22212, Korea; [email protected] (D.S.); [email protected] (J.N.) 2 Materials Architecturing Research Center, Korea Institute of Science and Technology, Seoul 02792, Korea; [email protected] 3 Division of Nano & Information Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Korea 4 Research Institute of Industrial Technology Convergence, Korea Institute of Industrial Technology, Ansan 15588, Korea * Correspondence: [email protected] (H.L.); [email protected] (M.K.) These authors equally contributed to this work. y Received: 3 April 2020; Accepted: 23 April 2020; Published: 4 May 2020 Abstract: This review provides detailed fundamental principles of X-ray-based characterization methods, i.e., X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, and near-edge X-ray absorption fine structure, and the development of different techniques based on the principles to gain deeper understandings of chemical structures in polymeric materials. Qualitative and quantitative analyses enable obtaining chemical compositions including the relative and absolute concentrations of specific elements and chemical bonds near the surface of or deep inside the material of interest. More importantly, these techniques help us to access the interface of a polymer and a solid material at a molecular level in a polymer nanocomposite. The collective interpretation of all this information leads us to a better understanding of why specific material properties can be modulated in composite geometry. -
Depleted Uranium Technical Brief
Disclaimer - For assistance accessing this document or additional information,please contact [email protected]. Depleted Uranium Technical Brief United States Office of Air and Radiation EPA-402-R-06-011 Environmental Protection Agency Washington, DC 20460 December 2006 Depleted Uranium Technical Brief EPA 402-R-06-011 December 2006 Project Officer Brian Littleton U.S. Environmental Protection Agency Office of Radiation and Indoor Air Radiation Protection Division ii iii FOREWARD The Depleted Uranium Technical Brief is designed to convey available information and knowledge about depleted uranium to EPA Remedial Project Managers, On-Scene Coordinators, contractors, and other Agency managers involved with the remediation of sites contaminated with this material. It addresses relative questions regarding the chemical and radiological health concerns involved with depleted uranium in the environment. This technical brief was developed to address the common misconception that depleted uranium represents only a radiological health hazard. It provides accepted data and references to additional sources for both the radiological and chemical characteristics, health risk as well as references for both the monitoring and measurement and applicable treatment techniques for depleted uranium. Please Note: This document has been changed from the original publication dated December 2006. This version corrects references in Appendix 1 that improperly identified the content of Appendix 3 and Appendix 4. The document also clarifies the content of Appendix 4. iv Acknowledgments This technical bulletin is based, in part, on an engineering bulletin that was prepared by the U.S. Environmental Protection Agency, Office of Radiation and Indoor Air (ORIA), with the assistance of Trinity Engineering Associates, Inc. -
Surface Reactions and Chemical Bonding in Heterogeneous Catalysis
Surface reactions and chemical bonding in heterogeneous catalysis Henrik Öberg Doctoral Thesis in Chemical Physics at Stockholm University 2014 Thesis for the Degree of Doctor of Philosophy in Chemical Physics Department of Physics Stockholm University Stockholm 2014 c Henrik Oberg¨ ISBN 978-91-7447-893-8 Abstract This thesis summarizes studies which focus on addressing, using both theoretical and experimental methods, fundamental questions about surface phenomena, such as chemical reactions and bonding, related to processes in heterogeneous catalysis. The main focus is on the theoretical approach and this aspect of the results. The included articles are collected into three categories of which the first contains detailed studies of model systems in heterogeneous catalysis. For example, the trimerization of acetylene adsorbed on Cu(110) is measured using vibrational spectroscopy and modeled within the framework of Density Functional Theory (DFT) and quantitative agreement of the reaction barriers is obtained. In the second category, aspects of fuel cell catalysis are discussed. O2 dissociation is rate-limiting for the reduction of oxygen (ORR) under certain conditions and we find that adsorbate-adsorbate interactions are decisive when modeling this reaction step. Oxidation of Pt(111) (Pt is the electrocatalyst), which may alter the overall activity of the catalyst, is found to start via a PtO-like surface oxide while formation of a-PtO2 trilayers precedes bulk oxidation. When considering alternative catalyst materials for the ORR, their stability needs to be investigated in detail under realistic conditions. The Pt/Cu(111) skin alloy offers a promising candidate but segregation of Cu atoms to the surface is induced by O adsorption. -
A Structural and Spectroscopic Study of the First Uranyl Selenocyanate, [Et4n]3[UO2(Ncse)5]
inorganics Article A Structural and Spectroscopic Study of the First Uranyl Selenocyanate, [Et4N]3[UO2(NCSe)5] Stefano Nuzzo, Michelle P. Browne, Brendan Twamley, Michael E. G. Lyons and Robert J. Baker * School of Chemistry, Trinity College, University of Dublin, 2 Dublin, Ireland; [email protected] (S.N.); [email protected] (M.P.B.); [email protected] (B.T.); [email protected] (M.E.G.L.) * Correspondence: [email protected]; Tel.: +353-1-896-3501; Fax: +353-1-671-2826 Academic Editors: Stephen Mansell and Steve Liddle Received: 30 October 2015; Accepted: 4 February 2016; Published: 16 February 2016 Abstract: The first example of a uranyl selenocyanate compound is reported. The compound [Et4N]3[UO2(NCSe)5] has been synthesized and fully characterized by vibrational and multinuclear (1H, 13C{1H} and 77Se{1H}) NMR spectroscopy. The photophysical properties have also been recorded and trends in a series of uranyl pseudohalides discussed. Spectroscopic evidence shows that the U–NCSe bonding is principally ionic. An electrochemical study revealed that the reduced uranyl(V) species is unstable to disproportionation and a ligand based oxidation is also observed. The structure of [Et4N]4[UO2(NCSe)5][NCSe] is also presented and Se¨ ¨ ¨ H–C hydrogen bonding and Se¨ ¨ ¨ Se chalcogen–chalcogen interactions are seen. Keywords: uranyl; structural determination; photophysics 1. Introduction The chemistry of uranium in its highest oxidation state has held scientists fascination for a long 2+ period of time. The uranyl moiety, [UO2] , is well studied in aqueous phases due, in part, to relevance in the nuclear waste treatment. Moreover, the photophysical properties of uranyl were first used in ancient roman times in colored glass [1], whilst comprehensive understanding of the bonding, and therefore photophysical properties, has come from both experiment and theory. -
Procedure for Determining Uranium, Plutonium and Americium by Extraction-Chromatographic Procedures
Procedure for determining uranium, plutonium and americium by extraction-chromatographic procedures H-U/Pu/Am-AWASS-01 Authors: M. Beyermann D. Obrikat Federal coordinating office for drinking water, groundwater, wastewater, sludge, waste and wastewater of nuclear power plants (Leitstelle für die Überwachung der Radioaktivität in Trinkwasser, Grundwasser, Abwasser, Klärschlamm, Reststoffen und Abfällen) ISSN 1865-8725 Version October 2000 Procedures manual for monitoring of radioactive substances in the environment and of external radiation (Messanleitungen für die „Überwachung radioaktiver Stoffe in der Umwelt und externer Strahlung“) H-U/Pu/Am-AWASS-01-01 Procedure for determining uranium, plutonium and americium by means of extraction- chromatographic procedures 1 Scope This procedure serves to simultaneously determine the uranium isotopes U-234, U-235 and U-238, the plutonium isotopes Pu-238, Pu-239 and Pu-240, as well as the americium isotope Am-241 in samples of wastewater from nuclear facilities. It furthermore offers an option of determining the curium isotopes Cm-242 and Cm-244 without further effort. For determining Pu-241, reference is made to pro- cedure H-Pu-241-AWASS-01 of these measuring instructions. 2 Sampling As far as sampling is concerned, reference is made to procedure H-SPEKT- AWASS-01 of these measuring instructions. The sample of the wastewater to be analysed is acidified with ca. 10 ml of concentrated nitric acid (14 mol·l-1) per litre to a pH of about 1. The stability of the acidic reaction needs to be monitored, in particular if the sample is stored for an extended period of time. This procedure ensures that a detection limit of 0,05 Bq·l-1 for alpha-emitters is reached in a sample volume of 0,1 litres to 0,25 litres and thus complies with the nuclear safety standard 1504 of the Nuclear Safety Standards Commission (1). -
Inorganic Chemistry for Dummies® Published by John Wiley & Sons, Inc
Inorganic Chemistry Inorganic Chemistry by Michael L. Matson and Alvin W. Orbaek Inorganic Chemistry For Dummies® Published by John Wiley & Sons, Inc. 111 River St. Hoboken, NJ 07030-5774 www.wiley.com Copyright © 2013 by John Wiley & Sons, Inc., Hoboken, New Jersey Published by John Wiley & Sons, Inc., Hoboken, New Jersey Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permis- sion of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley. com/go/permissions. Trademarks: Wiley, the Wiley logo, For Dummies, the Dummies Man logo, A Reference for the Rest of Us!, The Dummies Way, Dummies Daily, The Fun and Easy Way, Dummies.com, Making Everything Easier, and related trade dress are trademarks or registered trademarks of John Wiley & Sons, Inc. and/or its affiliates in the United States and other countries, and may not be used without written permission. All other trade- marks are the property of their respective owners. John Wiley & Sons, Inc., is not associated with any product or vendor mentioned in this book. -
Anion Photoelectron Spectroscopic and Relativistic Coupled-Cluster Studies of − Uranyl Dichloride Anion, Uo2cl2 Mary Marshall, Zhaoguo Zhu, Junzi Liu, Kit H
Journal of Molecular Spectroscopy 379 (2021) 111496 Contents lists available at ScienceDirect Journal of Molecular Spectroscopy journal homepage: www.elsevier.com/locate/yjmsp Article Anion photoelectron spectroscopic and relativistic coupled-cluster studies of * uranyl dichloride anion, UO2Cl2 Mary Marshall, Zhaoguo Zhu, Junzi Liu, Kit H. Bowen, Lan Cheng < Department of Chemistry, The Johns Hopkins University, Baltimore, MD 21218, USA ARTICLEINFO ABSTRACT Keywords: A joint relativistic coupled-cluster and experimental photoelectron (PE) spectroscopic study of the uranyl Coupled-cluster * dichloride anion, UO2Cl2 , is reported. Sophisticated electronic-structure calculations predict the photodetach- Anion photoelectron * ment of UO2Cl to involve a U 5f electron and to be followed by significant geometry relaxation. Therefore, the Uranyl 2 adiabatic electron affinity (EAa) of the uranyl dichloride neutral molecule, UO2Cl2, and the vertical detachment * energy (VDE) of its anion, UO2Cl2 , provide valuable information about its uranium 5f orbital energies. The EAa value was computed to be 3.15 eV. The VDE value was calculated to be 3.55 eV by augmenting the computed EAa with a shift derived from a Franck–Condon simulation using coupled-cluster potential energy surfaces. The VDE, which corresponds to the highest intensity peak in the PE spectrum, was measured to be 3.69 , 0.20 eV, in good agreement with the computed value. The origin transition in the PE spectrum, whose electron binding energy corresponds to the EAa, was assigned to the feature at 3.2 , 0.20 eV, consistent with the computed EAa. 1. Introduction at 20323 cm*1 with nearly harmonic vibrational progressions at a frequency of 840 cm*1 [15]. -
(XPS) • X-Ray Photoelectron Spectroscopy
Introduction to X-ray Photoelectron Spectroscopy (XPS) • X-ray Photoelectron Spectroscopy (XPS), also known as Electron Spectroscopy for Chemical Analysis (ESCA) is a widely used technique to investigate the chemical composition of surfaces. • XPS which makes use of the photoelectric effect, was developed in the mid-1960’s by Kai Siegbahn and his research group at the University of Uppsala, Sweden. Photoemission of Electrons Ejected Photoelectron Incident X-ray Free Electron Level (vacuum) Conduction Band Fermi Level Valence Band ¾ XPS spectral lines are identified by the shell from which the electron was ejected 2p L2,L3 (1s, 2s, 2p, etc.). ¾ The ejected photoelectron has kinetic 2s L1 energy: ¾ KE= hv – BE - φ 1s K 1s K ¾ Following this process, the atom will release energy by the emission of a photon or Auger Electron. Auger Electron Emission Free Electron Level Conduction Band Conduction Band Fermi Level Valence Band Valence Band 2p 2p L2,L3 2s 2s L1 1s 1s K ¾ L electron falls to fill core level vacancy (step 1). ¾ KLL Auger electron emitted to conserve energy released in step 1. ¾ The kinetic energy of the emitted Auger electron is: KE=E(K)-E(L2)-E(L3). XPS Energy Scale - Binding energy BEBE == hvhv -- KEKE -- ΦΦspec Where: BE= Electron Binding Energy KE= Electron Kinetic Energy Φspec= Spectrometer Work Function Photoelectron line energies: Not Dependent on photon energy. Auger electron line energies: Dependent on photon energy. XPS spectrum of Vanadium Auger electrons Note the stepped background • Only electrons close to surface -
Novel Heterometallic Uranyl-Transition Metal Materials: Structure, Topology, and Solid State Photoluminescence Properties † ‡ ‡ § Germań E
Article Cite This: Inorg. Chem. 2019, 58, 7243−7254 pubs.acs.org/IC Novel Heterometallic Uranyl-Transition Metal Materials: Structure, Topology, and Solid State Photoluminescence Properties † ‡ ‡ § Germań E. Gomez, J. August Ridenour, Nicole M. Byrne, Alexander P. Shevchenko, ‡ and Christopher L. Cahill*, † Instituto de Investigaciones en Tecnología Química (INTEQUI), Area de Química General e Inorganicá “Dr. G. F. Puelles,” Facultad de Química, Bioquímica y Farmacia, Chacabuco y Pedernera, Universidad Nacional de San Luis, Almirante Brown, 1455, 5700 San Luis, Argentina ‡ Department of Chemistry, The George Washington University, Science and Engineering Hall, 800 22nd Street, NW, Washington, DC 20052, United States § Samara Center for Theoretical Materials Science, Samara University, 34, Moskovskoye shosse, Samara, 443086, Russia *S Supporting Information ABSTRACT: Six new uranyl hybrid materials have been synthesized solvothermally ′ ′ ′ ′ ′′ utilizing the ligands 2,2 -bipyridine-3,3 -dicarboxylic acid (H2L) and 2,2 :6 ,2 -terpyridine (TPY). The six compounds are classified as either molecular complexes (I0O0 connectivity), · · [(UO2)(L)(TPY)] H2O(1), [Ni(TPY)2][(UO2)(L)2] 3H2O(2), and [Cu(TPY)2]- · − 0 3 [(UO2)(L)2] 3H2O(3), or 3D metal organic frameworks (MOFs, I O connectivity), · [Cu2(UO2)2(OH)(C2H3O2)(L)3(TPY)2] 6H2O(4), [Zn2(UO2)2(OH)(NO3)(C2H3O2)- · · (L)3(TPY)2] 4H2O(5), and Na[Ni(UO2)3(OH)(O)(L)3] 9H2O(6). A discussion of the influence of transition metal incorporation, chelating effects of the ligand, and synthesis conditions on the formation of uranyl materials is presented. The structure of compound 6 is of particular note due to large channel-like voids with a diameter of approximately 19.6 Å.