DOCSLIB.ORG

Nano-Optical Image-Making L a R E N E G ©2020 ISAST with Thisissue

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Nano-Optical Image-Making L a R E N E G ©2020 ISAST with Thisissue g e n e r a l a r t i c l e Nano-Optical Image-Making Morphologies, Devices, Speculations A l e k san d ra k A M I N S k A This article provides a technical overview of nano-optical image-making gies of the image, with work at the nanoscale currently a produced in collaboration between the author, engineering scientists focus of this activity. This area of research was explored in a at the Ciber Lab in Vancouver and the artists Christine Davis and Scott collaborative initiative I instigated and developed with Hao Lyall. It situates the work in relation to other optical technologies (such ABSTRACT as holographs), to the primary application of nano-optical images Jiang and Bozena Kaminska at the Ciber Lab at Simon Fraser as authentication devices and to other artistic practices concerning University in Vancouver, along with artists Christine Davis nanoscale interactions of light and matter. The paper articulates and Scott Lyall, each of whom has been working on studies the convergence of visual technologies and designed materials by of light, color and material throughout their career. Together explaining how the principles of structural color can be used for the we have been developing nano-optical images that material- production of images. Building a discussion on the shift from device ize in the convergence of visual technologies and designed to medium that is anchored around questions of remediation and reproducibility, it concludes with a speculation on informatic matters, materials, resulting in both material samples and specula- or the convergence of mediating functions at the surface of things. tive prototypes of something that could be described as a burgeoning optical medium. The ability to design materials at the nanoscale is providing MorphOlOgIeS Of scientists and artists alike with new ways of manipulating ORganic/desigNed Nano-Optics light and making color. The “blackest of black,” or what has come to be known as Vantablack [1], is one example of a Morphology (from the Greek morphé, or form) is concerned metamaterial pushing the established laws of chemistry and with forms and structures and is most frequently used in cer- physics for visual effect. Artists have in some cases conten- tain branches of linguistics and biology. The outcome of a sci- tiously claimed some of these for personal and exclusive use entific interest in shapes and their functions has notably led [2], but this control over color also extends to other fields. to the now-familiar detailed drawings of plants, animals and In the security industry, for example, there is a continuous other life-forms that have been the product of morphological search for cutting-edge image-making techniques and sub- studies since at least Robert Hooke’s Micrographia in 1665. It strates, especially in the sector interested in the production of has been well documented how these structural studies have visual devices, such as those used for authentication. There, been refined with every advance in optical technology, each technologies like next-generation holographs or UV inks are allowing the human eye to see what it previously could not developed for use in passports, credit cards, product labels [3]. Through optical devices like microscopes, form, struc- and other objects as a means to visually identify, legitimate ture and the shape of things gradually emerged from the lim- and secure. In this context, restricted access to the technical its of perception. With the development of microscopes that know-how required for producing complex visual effects is could reach into the molecular scale came the ability to see a necessary anticounterfeiting measure. Artists, scientists, the construction of matter itself [4]. One of the phenomena governments and industries alike are thus all interested in that was studied at this scale is biological iridescence, such the ongoing development and exclusivity of new technolo- as the shimmering blue wing of the morpho butterfly. What a nanoscale morphological study revealed is that the wings are in themselves transparent and the color comes not from Aleksandra Kaminska (researcher), Université de Montréal, Department of Communication, PO Box 6128, Downtown Station, Montreal, QC H3C 3J7 Canada. pigment but from structure: It is through the morphology Email: [email protected]. Web: www.aleksandrakaminska.com. of the wing—its form—that color is produced. This is called See www.mitpressjournals.org/toc/leon/53/2 for supplemental files associated structural color [5]. with this issue. Because of the way the light diffracts in the billions of ©2020 ISAST https://doi.org/10.1162/leon_a_01610 LEONARDO, Vol. 53, No. 2, pp. 167–173, 2020 167 Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/leon_a_01610 by guest on 30 September 2021 nano-sized structures that constitute the wing of the mor- In the business of authentication technologies, optical pho butterfly, it generally appears blue to the human eye. nano-images are called nano-optical variable devices (nano- In movement (i.e. when angles between structures, light OVDs), with colors and variability (morphing, iridescence) and eye shift), the points of contact tune in and out and the becoming ever-more precise and defined thanks to the on- color shimmers, or iridesces. The fact that the appearance going improvements in nanoscale engineering in designing is generally blue is significant, as is the implication that the specific shapes and forms [11]. OVDs, which include the term morpho refers to an idea of changing forms: morphing, common holograph, are characterized by their changeability, metamorphosis, etc. In the morpho butterfly, this applies not or iridescent visual effects, which tune in and out of focus as to a literal restructuring of the wing but to the variability they are tilted and placed under different light conditions. or instability in the color that is perceived, that is, in the However, holographs and nano-OVDs are produced using a iridescent quality of the blue. This iridescence—a mutabil- different technical principle: whereas holographs are based ity of perceived color—is the product of the fluid interac- on the recording, or inscription, of a whole image on a holo- tion between the environment (light) and angles of sight, or graphic film (substrate) with reflected laser light, the nano- “viewing geometry” [6]. Such iridescence exists only to the OVD’s visual effect comes from the structural forms of the extent of our ability to see it [7]. substrate itself. This is significant insofar as the scientific goal The study of iridescence is the study of optics, or “the long of nano-optical image research is not primarily to produce history of humanity’s struggle to control light” [8]. The mor- 3D representations (which is also a possibility) but rather to pho butterfly’s iridescent wing has served as an oft-referenced produce high-resolution images that can be seen accurately inspiration for nano-optical researchers. Engineering scien- under the widest-possible viewing angles, in effect working tists, extrapolating from the morphology of the wing, began to limit its color variability and improve brightness (color designing materials with specific nano-sized structures to intensity). The search for widest viewing angle and high reso- imitate the hole-based system of the butterfly to produce a lution is the search for a reliable form of representation and variety of colors through shifting forms and shapes. The re- reproduction, something more akin to a multipurpose film sulting substrates—what Giuliana Bruno might refer to as the that is used in analog cameras than to ambitions of producing “fabric of the visual” [9]—use nano-sized slits or holes that 3D representations. are designed to produce specific material encounters with The primary application of nano-OVDs has been as an light that generate precise “optical effects.” Because of these anticounterfeit device for documents, joining a lineage that nanoscale dimensions, light behaves and interacts not merely includes practices of microphotography and security print- as a beam or ray but rather through its constitutive parts— ing. The typical way of producing nano-OVDs for such use wavelengths, photons. As light hits the surface of this pixelated is through renewals of familiar techniques—lithography, canvas, it diffracts, refracts, reflects and transmits selectively embossing, stamping. First, a master of a wanted image (the so that the human eye sees certain colors at certain angles. “original”) is fabricated in a nickel stamp (using nanolithog- A number of artists have experimented with nano-optics raphy), which is then replicated through roll-to-roll emboss- in their work. Anish Kapoor has claimed exclusive rights to ing in a colorless polymer/plastic [12]. The optical image is Vantablack, but other artists have also worked to produce structurally integrated into the material: The color from each near-absolute blacks, such as Stuart Semple with his Black hole of the nanosubstrate is a direct outcome of the stamping 2.0 (2017), or Frederik de Wilde in his series Hostage (2010–), process. This technique means that to reproduce is to make a where black “grows” through the cultivation of carbon copy of a combined material-image each time. nanotubes. Kate Nichols meanwhile is producing iridescent While OVDs are in general difficult to reproduce (and thus nano-optical pigments using silver nanoparticles, showcased forge) because of their technical complexity, nano-OVDs for example in Doppelganger (2013), among other ongoing made in this way face specific challenges. First is a restriction works. Where the work in our collaboration differs, however, concerning the volume of production. To produce a nickel is that we are not producing pigment but surface: a canvas stamp requires significant investment of time, labor and re- that uses the logic of a system of holes, as in the butterfly sources—too much in fact to produce for one-off images and wing, for the making of color.
Load more

Recommended publications
  • In This Issue NIOSH Not Issuing New Recommended Exposure Limit For
    Volume 11, No. 2 • Summer 2016 Environmental Protection Agency (US EPA) and the Food and In This Issue Drug Administration (FDA) to require companies to submit data on worker exposures to nanosilver before products con- • Recent Government Briefs taining nanosilver are allowed into the marketplace. These • Reports, Reviews, White Papers, and Books groups also supported implementing controls to mitigate ex- • Hot-off-the-Presses: Peer-reviewed Research posures (e.g., eliminating exposure to nanosilver or using less- Articles of Note hazardous substances) and recommended that companies be • Upcoming Meetings and Conferences required to submit safety data on potential risks to workers • New Product Review (e.g., liver and lung effects). Specifically, these groups noted the need to address women's exposures to nanosilver (e.g., for reproductive endpoints), because most occupational studies Recent Government Briefs of this substance have focused on men. Link to the Risk Policy Report, by Reynolds: http://insideepa.com/risk-policy-report/niosh-for- goes-novel-limit-nanosilver-citing-insufficient-risk-da- NIOSH Not Issuing New Recommended ta Exposure Limit for Nanosilver The docket, including comments and supporting documenta- tion, can be accessed here: Based on the comments it received on the draft document https://www.regulations.gov/#!docketDetail;D=C "Health Effects of Occupational Exposure to Silver Nanomate- DC-2016-0001 rials," the National Institute for Occupational Safety and Health (NIOSH) has decided it will not issue a specific
    [Show full text]
  • EPIC Members Directory In
    clionixumotL88 EPIC Consortium Members Directory: 737 members Questions/Comments, please contact [email protected] This directory is updated every month. Latest revision: 15 September 2021 Table of contents 1. II-VI Incorporated ................................................................................................................ 20 2. III-V Lab ................................................................................................................................ 21 3. 3D AG................................................................................................................................... 21 4. 3photon ............................................................................................................................... 21 5. 3SP Technologies ................................................................................................................. 21 6. 4isp ...................................................................................................................................... 22 7. 4JET Group ........................................................................................................................... 22 8. 603OPTX .............................................................................................................................. 22 9. 8photonics ........................................................................................................................... 23 10. Aarhus University ...............................................................................................................
    [Show full text]
  • Photoacoustic Characteristics of Carbon-Based Infrared Absorbers
    Photoacoustic characteristics of carbon-based infrared absorbers Jussi Rossi1, Juho Uotila2, Sucheta Sharma3, Toni Laurila3, Roland Teissier4, Alexei Baranov4, Erkki Ikonen3,5 and Markku Vainio1,6 1 Photonics Laboratory, Physics Unit, Tampere University, Tampere, Finland 2 Patria Aviation Oy, Tampere, Finland 3 Metrology Research Institute, Aalto University, Espoo, Finland 4 IES, University of Montpellier, CNRS, 34095 Montpellier, France 5 VTT MIKES, Espoo, Finland 6 Department of Chemistry, University of Helsinki, Helsinki, Finland Contact: [email protected] or [email protected] Abstract We present an experimental comparison of photoacoustic responsivities of common highly absorbing carbon-based materials. The comparison was carried out with parameters relevant for photoacoustic power detectors and Fourier-transform infrared (FTIR) spectroscopy: we covered a broad wavelength range from the visible red to far infrared (633 nm to 25 µm) and the regime of low acoustic frequencies (< 1 kHz). The investigated materials include a candle soot-based coating, a black paint coating and two different carbon nanotube coatings. Of these, the low-cost soot absorber produced clearly the highest photoacoustic response over the entire measurement range. Keywords: Candle soot, carbon nanotubes, photoacoustic response Introduction In addition to its many applications in spectroscopy [1-4] and imaging [5,6], the photoacoustic (PA) effect is useful for electromagnetic power detection due to its wavelength independency and high detection sensitivity. In a typical photoacoustic optical power detector, the incident radiation is first modulated by a chopper and then directed through a window to a PA cell. The cell contains an optical absorber to generate an acoustic wave at the chopping frequency.
    [Show full text]
  • Defense 2045: Assessing the Future Security Environment And
    NOVEMBER 2015 1616 Rhode Island Avenue NW Washington, DC 20036 202-887-0200 | www.csis.org Defense 2045 Lanham • Boulder • New York • London 4501 Forbes Boulevard Assessing the Future Security Environment and Implications Lanham, MD 20706 301- 459- 3366 | www.rowman.com for Defense Policymakers Cover photo: Shutterstock.com A Report of the CSIS International Security Program AUTHOR ISBN 978-1-4422-5888-4 David T. Miller 1616 Rhode Island Avenue NW FOREWORD Washington,Ë|xHSLEOCy258884z DC 20036v*:+:!:+:! Joseph S. Nye Jr. 202-887-0200 | www.csis.org Blank Defense 2045 Assessing the Future Security Environment and Implications for Defense Policymakers AUTHOR David T. Miller FOREWORD Joseph S. Nye Jr. A Report of the CSIS International Security Program November 2015 Lanham • Boulder • New York • London 594-62791_ch00_3P.indd 1 11/6/15 7:13 AM hn hk io il sy SY ek eh About CSIS hn hk io il sy SY ek eh For over 50 years, the Center for Strategic and International Studies (CSIS) has worked to hn hk io il sy SY ek eh develop solutions to the world’s greatest policy challenges. ­Today, CSIS scholars are hn hk io il sy SY ek eh providing strategic insights and bipartisan policy solutions to help decisionmakers chart hn hk io il sy SY ek eh a course toward a better world. hn hk io il sy SY ek eh CSIS is a nonprofit organ ization headquartered in Washington, D.C. The Center’s 220 full- time staff and large network of affiliated scholars conduct research and analy sis and hn hk io il sy SY ek eh develop policy initiatives that look into the future and anticipate change.
    [Show full text]
  • Technological Change 2013-2016 Change Technological Publication of the Committee for the Future 2/2016
    technological change 2013-2016 publication of the committee for the future 2/2016 technological change 2013-2016 Preliminary investigation of the development of radical technologies after the 2013 review 2/2016 isbn 978-951-53-3616-3 (paperback) • isbn 978-951-53-3617-0 (pdf) issn 2342-6594 (printed) • issn 2342-6608 (web) TECHNOLOGICAL CHANGE 2013–2016 Preliminary investigation: Development of radical technologies after the review in 2013 (100 Opportunities For Finland And The World, Publication Of The Committee For The Future 11/2014) Risto Linturi publication of the committee for the future 2/2016 Cover: freeimageslive.com Back cover: Part of the Artwork Tulevaisuus, Väinö Aaltonen (1932), photo Vesa Lindqvist. Committee for the Future FI-00102 Parliament of Finland www.parliament.fi Helsinki 2016 ISBN 978-951-53-3616-3 (paperback) ISBN 978-951-53-3617-0 (PDF) ISSN 2342-6594 (printed) ISSN 2342-6608 (web) Contents Foreword ......................................................................................................................... 5 1 Introduction, summary of observations and recommendations ................................ 8 1.1 A Hundred New Opportunities for Finland: Radical Technological Solutions ...... 8 1.2 Crowdsourcing after the publication of TuVRad9/2013 and acknowledgements ..................................................................................................... 9 1.3 Objectives of the preliminary investigation ...................................................... 11 1.4 The fastest-progressing baskets in the TuvRad9/2013 Top 25 category .......... 12 1.5 The fastest-progressing baskets in the TuVRad9/2016 Top 26–100 category . 13 1.6 New baskets and fields of technology that are proposed for monitoring ........ 14 1.7 Structural improvements to the report ............................................................ 15 1.8 Regional and international application of the four-level model ....................... 16 1.9 Interactive updating of the report with the help of database .........................
    [Show full text]
  • Surface Modification of Metal-Organic Framework Nanoparticles for Biomedical Applications
    Dissertation zur Erlangung des Doktorgrades der Fakultät für Chemie und Pharmazie der Ludwig-Maximilians-Universität München Surface modification of metal-organic framework nanoparticles for biomedical applications Andreas Zimpel aus Rosenheim, Deutschland 2018 Preface Erklärung Diese Dissertation wurde im Sinne von § 7 der Promotionsordnung vom 28. November 2011 von Herrn Prof. Dr. Thomas Bein betreut. Eidesstattliche Versicherung Diese Dissertation wurde eigenständig und ohne unerlaubte Hilfe bearbeitet. München, den 03. August 2018 ____________________________ Andreas Zimpel Dissertation eingereicht am 28.06.2018 1. Gutachter: Prof. Dr. Thomas Bein 2. Gutachter: Dr. Stefan Wuttke Mündliche Prüfung am 24.07.2018 I Preface Danksagung Zu Beginn meiner Dissertation möchte ich einigen Leuten danken, ohne die das Erlangen meines Doktorgrades niemals zu Stande gekommen wäre. Als erstes möchte ich mich bei meinem Chef, Mentor und Freund Dr. Stefan Wuttke bedanken, ohne den ich ziemlich sicher nie zu diesem, sehr interessanten Forschungsgebiet der „Metall-organischen Gerüstverbindungen“ gekommen wäre. Danke, dass du mich auf meinem wissenschaftlichen Weg, von unserer ersten Begegnung und Zusammenarbeit als F- Praktikant von Christian Dietl in der organischen Chemie, über das PC-F-Praktikum und die Masterarbeit bis hin zu meiner Doktorarbeit, immer angetrieben und unterstützt hast. Besonders herzlicher Dank gilt meinem Doktorvater, Prof. Dr. Thomas Bein für die Möglichkeit meine Dissertation in seiner Arbeitsgruppe anfertigen zu dürfen, für all die finanzielle und wissenschaftliche Unterstützung über die Jahre meiner Promotion, sowie bereits während meiner Masterarbeit. Bei beiden möchte ich mich auch speziell für die Chancen bedanken, meine Forschungsarbeiten auf diversen nationalen und internationalen Konferenzen präsentieren zu dürfen. Diese haben mich nicht nur durch interessante Diskussionen mit anderen Doktoranden wissenschaftlich neu inspiriert, sondern auch menschlich gefestigt, indem ich gezwungen war dadurch meine Kontaktscheu Fremden gegenüber abzulegen.
    [Show full text]
  • Catching up with Carbon Japan Fights to Stay on Top of a Field It Pioneered
    NANOCARBON IN JAPAN SPOTLIGHT Catching up with carbon Japan fights to stay on top of a field it pioneered. BY TIM HORNYAK n September last year, a handful of Nagoya University. “It was the most exciting the stability and strength to build complex researchers were sitting around a com- moment I ever had in my life.” molecules — into new materials with useful puter monitor in chemist Kenchiro Itami’s Itami thinks he has good reason to be so properties, and it has built a strong industrial Ilab at Japan’s Nagoya University as one loaded excited. “The discovery of a new form of car- sector from those basic research efforts. a file showing the results of an X-ray crystal- bon has always opened up new science and But in the past decade or so, Japan has found lography scan. Within seconds, the room technology — fullerenes are a great example,” itself beset by international competition, as erupted: scientists were on their feet, cheering he says, referring to the all-carbon molecular progress in the field has shifted abroad. Now, and exchanging high fives. In front of them spheres created by scientists at Rice University Japanese researchers are fighting to maintain was a 3D representation of a carbon nanobelt in Houston, Texas, in 1985. their global prominence. — a new molecule of carbon that the team Chemists have indeed tried many things had successfully synthesized after 12 years of when it comes to constructing exotic forms, NO SMALL PEDIGREE ILLUSTRATION BY PETER HORVATH; PHOTOS: GETTY PHOTOS: HORVATH; PETER BY ILLUSTRATION painstaking effort.
    [Show full text]
  • Bioinspired Microstructured Polymer Surfaces with Antireflective Properties
    nanomaterials Article Bioinspired Microstructured Polymer Surfaces with Antireflective Properties Alexandre Emmanuel Wetzel 1 , Nuria del Castillo Iniesta 1, Einstom Engay 1, Nikolaj Kofoed Mandsberg 2,3, Celine Schou Dinesen 1, Bilal Rashid Hanif 1 , Kirstine Berg-Sørensen 3, Ada-Ioana Bunea 1,* and Rafael Taboryski 1 1 National Centre for Nano Fabrication and Characterization (DTU Nanolab), Technical University of Denmark, Ørsted Plads 347, 2800 Kongens Lyngby, Denmark; [email protected] (A.E.W.); [email protected] (N.d.C.I.); [email protected] (E.E.); [email protected] (C.S.D.); [email protected] (B.R.H.); [email protected] (R.T.) 2 Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN), Technical University of Denmark, Ørsted Plads 345C, 2800 Kongens Lyngby, Denmark; [email protected] 3 Department of Health Technology (DTU Health Tech), Technical University of Denmark, Ørsted Plads 345C, 2800 Kongens Lyngby, Denmark; [email protected] * Correspondence: [email protected]; Tel.: +45-29404623 Abstract: Over the years, different approaches to obtaining antireflective surfaces have been explored, such as using index-matching, interference, or micro- and nanostructures. Structural super black colors are ubiquitous in nature, and biomimicry thus constitutes an interesting way to develop antireflective surfaces. Moth-eye nanostructures, for example, are well known and have been successfully replicated using micro- and nanofabrication. However, other animal species, such as Citation: Wetzel, A.E.; del Castillo birds of paradise and peacock spiders, have evolved to display larger structures with antireflective Iniesta, N.; Engay, E.; Mandsberg, features. In peacock spiders, the antireflective properties of their super black patches arise from N.K.; Schou Dinesen, C.; Hanif, B.R.; relatively simple microstructures with lens-like shapes organized in tightly packed hexagonal arrays, Berg-Sørensen, K.; Bunea, A.-I.; which makes them a good candidate for cheap mass replication techniques.
    [Show full text]
  • Plant Surfaces: Structures and Functions for Biomimetic Innovations
    Nano-Micro Lett. (2017) 9:23 DOI 10.1007/s40820-016-0125-1 REVIEW Plant Surfaces: Structures and Functions for Biomimetic Innovations Wilhelm Barthlott1 . Matthias Mail1,2 . Bharat Bhushan3 . Kerstin Koch4 Received: 21 October 2016 / Accepted: 4 December 2016 Ó The Author(s) 2016. This article is published with open access at Springerlink.com Abstract An overview of plant surface structures and their evolution is presented. It combines surface chemistry and architecture with their functions and refers to possible biomimetic applications. Within some 3.5 billion years biological species evolved highly complex multifunctional surfaces for interacting with their environments: some 10 million living prototypes (i.e., estimated number of existing plants and animals) for engineers. The complexity of the hierarchical structures and their functionality in biological organisms surpasses all abiotic natural surfaces: even superhydrophobicity is restricted in nature to living organisms and was probably a key evolutionary step with the invasion of terrestrial habitats some 350–450 million years ago in plants and insects. Special attention should be paid to the fact that global environmental change implies a dramatic loss of species and with it the biological role models. Plants, the dominating group of organisms on our planet, are sessile organisms with large multifunctional surfaces and thus exhibit particular intriguing features. Superhydrophilicity and superhydrophobicity are focal points in this work. We estimate that superhydrophobic plant leaves (e.g., grasses) comprise in total an area of around 250 million km2, which is about 50% of the total surface of our planet. A survey of structures and functions based on own examinations of almost 20,000 species is provided, for further references we refer to Barthlott et al.
    [Show full text]
  • Design, Applications, and Processing of Synthetic Protein Nanoparticles
    Design, Applications, and Processing of Synthetic Protein Nanoparticles by Daniel F. Quevedo A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Biomedical Engineering) in the University of Michigan 2020 Doctoral Committee: Professor Joerg Lahann, Chair Professor Lola Eniola-Adefeso Assistant Professor Colin F. Greineder Professor Blanca H. Lapizco-Encinas, Rochester Institute of Technology Professor Peter Tessier Daniel F. Quevedo [email protected] ORCID iD: 0000-0001-5892-364X © Daniel F. Quevedo 2020 Dedication To Ma, Pa, and Miguel for their love and support and To Shannon, who is my everything, and without whom this thesis would not exist ii Acknowledgements First and foremost, I would like to convey my deepest thanks and gratitude to my advisor, Professor Joerg Lahann, for guidance, kindness, patience, and support, and without whom nothing contained in this dissertation would be possible. His keen scientific insight, gentle guiding hand, and uncanny ability to calm and reassure any student as soon as they enter his office, no matter what the problem is, got me through the last 5 years. I am honored and proud to have joined his lab and worked with him, from my time at the Karlsruhe Institute of Technology, all the way to being locked up in my apartment for the last few months of my PhD. I would also like to thank my committee members, Professor Lola Eniola-Adefeso, Professor Peter Tessier, Professor Colin F. Greineder, and Professor Blanca H. Lapizco-Encinas, for their help and guidance over the years. Whether it was classes, constantly asking for a meeting to check up on my progress, working with me to design experiments, or even having insightful conversations while driving me to the airport, their contributions have shaped me, my thoughts, and the contents of this dissertation.
    [Show full text]
  • Are We Ready for Spray-On Carbon Nanotubes?
    SUBMITTED TEXT Nature Nanotechnology Thesis column, June 2016 Are we ready for spray-on carbon nanotubes? As artists and manufacturers explore the use of spray-on carbon nanotube coatings, Andrew Maynard explores the state of the science around nanotube safety. Andrew D. Maynard Director, Risk Innovation Lab. School for the Future of Innovation in Society, Arizona State University, Tempe AZ, USA. Email: [email protected] Earlier this year, British sculptor, Anish Kapoor was given exclusive rights to use a new spray-on carbon nanotube-based paint. The material – produced by UK-based Surrey NanoSystems and marketed as Vantablack S-VIS – can be applied to a range of surfaces, and absorbs well over 99% of the light that falls onto it.1 It is claimed to be the world’s blackest paint, and there is growing interest in its use in works of art and high- end consumer products. It’s easy to see the appeal of Vantablack S-VIS. Apart from technical applications where stray reflections need to be suppressed, this is a material that potentially enables manufacturers and artists to give their products a unique aesthetic edge. Yet, having worked on carbon nanotube safety for some years, I was intrigued to see the material in a spray-paint designed to coat objects that people may possibly come into contact with. It was, after all, only a few years ago that journalists were asking if carbon nanotubes were the next asbestos.2 And while this is unlikely, concerns over the possible health impacts of the material persist. Safety concerns of purposely manufactured carbon nanotubes began in the 1990’s.
    [Show full text]
  • Breakdown of Native Oxide Enables Multifunctional, Free-Form Carbon Nanotube−Metal Hierarchical Architectures † ‡ † Kehang Cui*, , and Brian L
    Research Article Cite This: ACS Appl. Mater. Interfaces XXXX, XXX, XXX−XXX www.acsami.org Breakdown of Native Oxide Enables Multifunctional, Free-Form Carbon Nanotube−Metal Hierarchical Architectures † ‡ † Kehang Cui*, , and Brian L. Wardle*, † Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02134, United States ‡ School of Materials Science and Engineering, State Key Laboratory of Metal-Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China *S Supporting Information ABSTRACT: Passive oxide layers on metal substrates impose remarkable interfacial resistance for electron and phonon transport. Here, a scalable surface activation process is presented for the breakdown of the passive oxide layer and the formation of nanowire/nanopyramid structured surfaces on metal substrates, which enables high-efficiency catalysis of high-crystallinity carbon nanotubes (CNTs) and the direct integration of the CNT−metal hierarchical architectures with flexible free-form configurations. The CNT−metal hierarchical architecture facilitates a dielectric free-energy-carrier transport pathway and blocks the reformation of passive oxide layer, and thus demonstrates a 5-fold decrease in interfacial electrical resistance with 66% increase in specific surface area compared with those without surface activation. Moreover, the CNT−metal hierarchical architectures demonstrate omnidirectional blackbody photoabsorption with the reflectance of 1 × 10−5 over the range from ultraviolet to terahertz region,
    [Show full text]