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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Aggregation and stability of nanoscale plastics in aquatic environment.
TL;DR: Results showed that salt types and ionic strength had significant effects on the stability of both polyethylene and polystyrene nanoscale plastics, while pH had none, indicating that significant aqueous transport of nanoscALE plastics will be possible in natural surface waters.
Journal ArticleDOI
The Toxic Truth About Carbon Nanotubes in Water Purification: a Perspective View
TL;DR: A CNT safety clock is proposed that could form the basis of an acceptable CNTSafety guidelines and several new risk analysis roots and framework extrapolations from CNT-based water purification technologies are suggested.
Journal ArticleDOI
Synthesis and spectroscopic characterization of solution processable highly ordered polythiophene–carbon nanotube nanohybrid structures
TL;DR: Evidence that the crystallinity of rrP3HT is enhanced in the presence of SWNTs, which introduces a reduced optical band gap and increased carrier mobility in the polymer, can explain the low efficiency of P3HT-SWNT solar cells produced to date.
Journal ArticleDOI
Harvesting photons with carbon nanotubes
TL;DR: In this paper, carbon nanotubes have emerged as new architectures for designing light-harvesting assemblies and they have been used as photoresponsive electrode materials and their role in the conversion of light energy into electricity is discussed.
Journal ArticleDOI
Triplet state absorption in carbon nanotubes: a TD-DFT study.
TL;DR: Striking similarity of the electronic features between CNTs and pi-conjugated polymers are demonstrated and explicit guidelines for spectroscopic detection of CNT triplet states are provided.
References
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Journal ArticleDOI
CHARMM: A program for macromolecular energy, minimization, and dynamics calculations
Bernard R. Brooks,Robert E. Bruccoleri,Barry D. Olafson,David J. States,S. Swaminathan,Martin Karplus +5 more
TL;DR: The CHARMM (Chemistry at Harvard Macromolecular Mechanics) as discussed by the authors is a computer program that uses empirical energy functions to model macromolescular systems, and it can read or model build structures, energy minimize them by first- or second-derivative techniques, perform a normal mode or molecular dynamics simulation, and analyze the structural, equilibrium, and dynamic properties determined in these calculations.
Journal ArticleDOI
MOLSCRIPT: a program to produce both detailed and schematic plots of protein structures
TL;DR: The MOLSCRIPT program as discussed by the authors produces plots of protein structures using several different kinds of representations, including simple wire models, ball-and-stick models, CPK models and text labels.
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.