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Search Publications by: Jeffrey Fagan (Fed)

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Displaying 76 - 100 of 197

Differentiating Left- and Right-Handed Carbon Nanotubes by DNA

December 28, 2016
Author(s)
Ming Zheng, Geyou Ao, Jason K. Streit, Jeffrey A. Fagan
The emergence of macromolecules of defined structures is a crucial step in the evolution of life. The mechanism by which these structures are selected from astronomical numbers of biopolymer sequences has long been a topic of controversy1,2. Experimenting

Enhancing Single-Wall Carbon Nanotube Properties Through Controlled Endohedral Filling

May 10, 2016
Author(s)
Jochen I. Campo, Yanmei Piao, Stephanie Lam, Christopher Stafford, Jason K. Streit, Jeffrey R. Simpson, Angela R. Hight Walker, Jeffrey Fagan
Chemical control of the endohedral volume of single-wall carbon nanotubes (SWCNTs) via liquid-phase filling is demonstrated to be a facile strategy to controllably modify properties of the nanotubes in manners significant for processing and proposed

Quantification of carbon nanotubes in environmental matrices: Current capabilities, case studies, and future improvements

April 6, 2016
Author(s)
Elijah J. Petersen, D. X. Flores-Cervantes, Thomas Bucheli, Lindsay C. Elliott, Jeffrey A. Fagan, Alexander Gogos, Shannon Hanna, Antonio R. Montoro Bustos, Desiree L. Plata, Vytautas Reipa, Paul Westerhoff, Michael R. Winchester, Elisabeth Mansfield
Carbon nanotubes (CNTs) have numerous exciting potential applications approaching commercialization. As such, quantitative measurements of CNTs in key environmental matrices (water, soil, sediment, and biological tissues) are needed to address concerns

The Nature of Record Efficiency Fluid-Processed Nanotube-Silicon Heterojunctions

April 20, 2015
Author(s)
Jeffrey A. Fagan, Erik K. Hobbie, John M. Harris, Matthew R. Semler
The dark transport characteristics of heterojunctions assembled from type, chirality and length-purified single-wall carbon nanotubes (SWCNTs) are used to clarify the nature of nanotube-silicon diodes and solar cells. The freestanding films show remarkable

How Large Can We Go? Isolation of > 1 nm Diameter Single-Wall Carbon Nanotubes Species using Aqueous Two Phase Extraction

April 14, 2015
Author(s)
Jeffrey A. Fagan, Erik Haroz, Rachelle Ihly, Hui Gui, Jeffrey Blackburn, Jeffrey R. Simpson, Stephen K. Doorn, Stephanie Lam, Angela R. Hight Walker, Ming Zheng
We demonstrate the effective separation of near-monochiral single-wall carbon nanotube (SWCNT) species with diameters > 1 nm through multi-stage aqueous two phase extraction (ATPE), and report an empirical function for the surfactant concentrations at

Redox sorting of carbon nanotubes

March 17, 2015
Author(s)
Hui Gui, Jason K. Streit, Jeffrey Fagan, Angela R. Hight Walker, Chongwu Zhou, Ming Zheng
This work expands the redox chemistry of single-wall carbon nanotube (SWCNT) by investigating its role in a number of SWCNT sorting processes. Using a polyethylene glycol (PEG)/dextran (DX) aqueous two-phase system, we show that electron-transfer reaction

Analytical Ultracentrifugation of Carbon Nanotubes

November 26, 2014
Author(s)
Jeffrey A. Fagan
Sedimentation velocity (SV) experiments on dispersed nanoparticles are a powerful method for determining otherwise hard to evaluate properties of the nanoparticle such as the density and size of the adsorbed interfacial layer, or for a direct evaluation of

Hydrodynamic Behavior of Carbon Nanotubes and Characterization of Length Distributions

February 28, 2014
Author(s)
Carlos A. Silvera Batista, Ming Zheng, Constantine Y. Khripin, Xiaomin X. Tu, Jeffrey Fagan
The sedimentation behavior of SWCNTs was studied through analytical ultracentrifugation. SWCNTs were dispersed with the aid of surfactants, doubly sorted by density and length to produce samples with invariant diameter distributions and aspect ratios that

Isolation of Specific Small Diameter Single-Wall Carbon Nanotube Species via Aqueous Two-Phase Extraction

January 21, 2014
Author(s)
Jeffrey A. Fagan, Constantine Y. Khripin, Carlos A. Silvera Batista, Jeffrey R. Simpson, Angela R. Hight Walker, Ming Zheng
Aqueous two-phase extraction (ATPE) is demonstrated to enable isolation of multiple semiconducting and metallic single-wall carbon nanotube species from a small diameter synthetic mixture. Separation by ATPE is rapid and robust, with remarkable tunability