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Sorting of single-wall carbon nanotubes by their electronic and atomic structures in liquid phases is reviewed in this chapter. We first introduce the sorting problem, then provide an overview of several sorting methodologies, following roughly the
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
Ming Zheng, Xiangyun Qiu, Fuyou Ke, Raju Timsina, Constantine Y. Khripin
DNA-carbon nanotube (DNA-CNT) hybrids are nanometer-sized, highly-charged, rod-like molecules with complex surface chemistry, and their behaviors in aqueous solutions are governed by multifactorial interactions with both solvent and co-solutes. We have
Yanmei Piao, Jeffrey R. Simpson, Jason K. Streit, Geyou Ao, Ming Zheng, Angela R. Hight Walker
Relative intensities of resonant Raman spectral features, specifically the radial breathing mode (RBM) and G modes, of eleven chirality-enriched single-wall carbon nanotube (SWCNT) species were established under second-order optical transition excitation
Accurate characterization of dispersed-phase nanoparticle properties such as density, size, solvation, and charge is necessary for their utilization in applications such as medicine, energy and materials. Herein, analytical ultracentrifugation is used to
Semiconducting single-wall carbon nanotubes (SWCNTs) with long lengths are highly desirable for many applications such as thin film transistors and circuits. Previous reported length sorting techniques usually require sophisticated instrumentations and are
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
Purification of single-chirality single-wall carbon nanotubes (SWCNTs)from their synthetic mixture is a prerequisite for many applications. DNA-controlled carbon nanotube (CNT) purification has evolved over a decade along with other separation techniques
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
Sorting single-wall carbon nanotubes (SWCNTs) of different chiralities is both scientifically interesting and technologically important. Recent studies have shown that polymer aqueous two-phase extraction is a very effective way to achieve nanotube sorting
Ming Zheng, Min Zhang, Constantine Y. Khripin, Jeffrey Fagan, Yoichiro Ito
Development of simple processes to fractionate synthetic mixtures of single-wall carbon nanotubes (SWCNTs) into individual species is crucial to many applications. Existing methods for single- chirality SWCNT purification are cumbersome, often requiring
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
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
Elijah J. Petersen, Xiaomin X. Tu, M Miral Dizdar, Ming Zheng, Bryant C. Nelson
Ultrasonication is a physical process known to generate abundant levels of oxygen-derived species such as hydroxyl radicals, hydrogen atoms, and hydrogen peroxide. When used to process DNA solutions, these highly reactive hydroxyl radicals can react with
Jeffrey A. Fagan, Ming Zheng, Jeffrey R. Simpson, Vinayak Rastogi, Constantine Y. Khripin, Carlos A. Silvera Batista, Angela R. Hight Walker
The structure and density of the bound interfacial surfactant layer and associated hydration shell were investigated using analytical ultracentrifugation for length and chirality purified (6,5) single-wall carbon nanotubes (SWCNTs) in three different bile
Constantine Y. Khripin, Xiaomin X. Tu, Jeffrey A. Fagan, Ming Zheng
Length fractionation of colloidal carbon nanotube dispersions is required for many studies. Size- exclusion chromatography (SEC) has been reported as a reliable method for high resolution length fractionation of DNA-dispersed single-wall carbon nanotubes
Carbon nanotubes possess superior electrical and optical properties and hold great promise for electronic and biomedical applications1-10. The electronic properties of carbon nanotubes strongly depend on their chirality, with 1/3 being metallic1, 2/3 being
Constantine Y. Khripin, Xiaomin X. Tu, John Howarter, Jeffrey A. Fagan, Ming Zheng
Determination of the colloid concentration for a given single-wall carbon nanotube (SWCNT) dispersion is a basic requirement for many studies. The commonly used optical absorption based concentration measurement is complicated by the spectral change due to
Jason Streit, Sergei M. Bachilo, Anton V. Naumov, Constantine Y. Khripin, Ming Zheng, R B. Weisman
A new method is demonstrated for measuring the length distributions of dispersed single-walled carbon nanotube (SWCNT) samples by analyzing diffusional motions of many individual nanotubes in parallel. In this method, termed Length Analysis by Nanotube
Elijah J. Petersen, Xiaomin X. Tu, M Miral Dizdar, Ming Zheng, Bryant C. Nelson
Ultrasonication is a physical process known to generate abundant levels of oxygen-derived species such as hydroxyl radicals, hydrogen atoms, and hydrogen peroxide. Highly reactive hydroxyl radicals can react with DNA to generate strand breaks and a
Constantine Y. Khripin, Nicholas A. Arnold-Medabalimi, Ming Zheng
Emerging applications require single-wall carbon nanotubes (SWCNTs) of welldefined length. Yet the use of length-defined SWCNTs is limited, in part due to the lack of an easily accessible materials preparation method. Here, we present a new strategy for
A long-held but untested fundamental assumption in Raman spectroscopy of carbon nanotubes is that intensities arising from resonance with incident and scattered photons are equal. We present here the first complete Raman excitation profiles (REPs) for the