Journal ArticleDOI
Band gap fluorescence from individual single-walled carbon nanotubes.
Michael J. O'Connell,Sergei M. Bachilo,Chad B. Huffman,Valerie C. Moore,Michael S. Strano,Erik H. Haroz,Kristy L. Rialon,Peter J. Boul,William H. Noon,Carter Kittrell,Jianpeng Ma,Jianpeng Ma,Robert H. Hauge,R. Bruce Weisman,Richard E. Smalley +14 more
TLDR
At pH less than 5, the absorption and emission spectra of individual nanotubes show evidence of band gap–selective protonation of the side walls of the tube, which is readily reversed by treatment with base or ultraviolet light.Abstract:
Fluorescence has been observed directly across the band gap of semiconducting carbon nanotubes. We obtained individual nanotubes, each encased in a cylindrical micelle, by ultrasonically agitating an aqueous dispersion of raw single-walled carbon nanotubes in sodium dodecyl sulfate and then centrifuging to remove tube bundles, ropes, and residual catalyst. Aggregation of nanotubes into bundles otherwise quenches the fluorescence through interactions with metallic tubes and substantially broadens the absorption spectra. At pH less than 5, the absorption and emission spectra of individual nanotubes show evidence of band gap-selective protonation of the side walls of the tube. This protonation is readily reversed by treatment with base or ultraviolet light.read more
Citations
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Journal ArticleDOI
Near-infrared photoconductive and photovoltaic devices using single-wall carbon nanotubes in conductive polymer films
TL;DR: In this article, the authors have fabricated prototypical Al/single-wall carbon nanotube (SWNT)-polymer/indium tin oxide thin-film devices that exhibit promising photoconductive and photovoltaic responses in a broad spectral range, typically from 300to1600nm.
Journal ArticleDOI
Determination of the surface coverage of exfoliated carbon nanotubes by surfactant molecules in aqueous solution
TL;DR: This work applies four experimental methods based on thermogravimetric analysis, UV-vis spectroscopy, surface tension measurements, and a variant of Maron's titration to aqueous mixtures of carbon nanotubes and the surfactant sodium dodecyl sulfate to consistently find a surface coverage of between 1.5 and 2 g of surfactants per gram of carbon Nanotubes.
Patent
Sidewall functionalization of carbon nanotubes with organosilanes for polymer composites
Enrique V. Barrera,Jiang Zhu,Lei Zhang,Valery N. Khabashesku,Johm Margrave,John L. Margrave,Jong Dae Kim +6 more
TL;DR: In this article, a method of functionalizing carbon nanotubes (CNTs) with organosilane species, wherein such functionalization enables fabrication of advanced polymer composites, is presented.
Journal ArticleDOI
Ab initio study of vibrational dephasing of electronic excitations in semiconducting carbon nanotubes.
TL;DR: Phonon-induced dephasing of electronic transitions in semiconducting single-wall carbon nanotubes (CNT) is investigated by ab initio molecular dynamics, suggesting that the defects can be identified in CNTs by broadened optical bands.
Patent
Optical component array having adjustable curvature
TL;DR: In this article, the curvature of an array of optical components on, embedded, or partially embedded in, a deformable substrate is adjusted by applying a force to the substrate.
References
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Bernard R. Brooks,Robert E. Bruccoleri,Barry D. Olafson,David J. States,S. Swaminathan,Martin Karplus +5 more
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Journal ArticleDOI
Crystalline Ropes of Metallic Carbon Nanotubes
Andreas Thess,R. S. Lee,Pavel Nikolaev,Hongjie Dai,Pierre Petit,J. Robert,Chunhui Xu,Young Hee Lee,Seong-Gon Kim,Andrew G. Rinzler,Daniel T. Colbert,Gustavo E. Scuseria,David Tománek,John E. Fischer,Richard E. Smalley +14 more
TL;DR: X-ray diffraction and electron microscopy showed that fullerene single-wall nanotubes (SWNTs) are nearly uniform in diameter and that they self-organize into “ropes,” which consist of 100 to 500 SWNTs in a two-dimensional triangular lattice with a lattice constant of 17 angstroms.
Book
Science of fullerenes and carbon nanotubes
TL;DR: In this paper, the authors present a detailed overview of the properties of Fullerenes and their properties in surface science applications, such as scanning tunnel microscopy, growth and fragmentation studies, and chemical synthesis.
Journal ArticleDOI
Constant pressure molecular dynamics simulation: The Langevin piston method
TL;DR: In this paper, a new method for performing molecular dynamics simulations under constant pressure is presented, which is based on the extended system formalism introduced by Andersen, the deterministic equations of motion for the piston degree of freedom are replaced by a Langevin equation; a suitable choice of collision frequency then eliminates the unphysical "ringing" of the volume associated with the piston mass.