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Alexander B. Artyukhin

Bio: Alexander B. Artyukhin is an academic researcher from State University of New York College of Environmental Science and Forestry. The author has contributed to research in topics: Carbon nanotube & Nanotube. The author has an hindex of 23, co-authored 43 publications receiving 3734 citations. Previous affiliations of Alexander B. Artyukhin include University of Texas Southwestern Medical Center & Lawrence Livermore National Laboratory.

Papers
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Journal ArticleDOI
19 May 2006-Science
TL;DR: Gas and water flow measurements through microfabricated membranes in which aligned carbon nanotubes with diameters of less than 2 nanometers serve as pores enable fundamental studies of mass transport in confined environments, as well as more energy-efficient nanoscale filtration.
Abstract: We report gas and water flow measurements through microfabricated membranes in which aligned carbon nanotubes with diameters of less than 2 nanometers serve as pores. The measured gas flow exceeds predictions of the Knudsen diffusion model by more than an order of magnitude. The measured water flow exceeds values calculated from continuum hydrodynamics models by more than three orders of magnitude and is comparable to flow rates extrapolated from molecular dynamics simulations. The gas and water permeabilities of these nanotube-based membranes are several orders of magnitude higher than those of commercial polycarbonate membranes, despite having pore sizes an order of magnitude smaller. These membranes enable fundamental studies of mass transport in confined environments, as well as more energy-efficient nanoscale filtration.

2,637 citations

Journal ArticleDOI
10 Jan 2004-Langmuir
TL;DR: These multilayer polyelectrolyte shells on individual carbon nanotubes introduce nearly unlimited opportunities for the incorporation of various functionalities into nanotube devices, which, in turn, opens up the possibility of building more complex multicomponent structures.
Abstract: Carbon nanotubes have been featured prominently in the nanotechnology research for some time, yet robust strategies for noncovalent chemical modification of the nanotube surface are still missing. Such strategies are essential for the creation of functional device architectures. Here, we present a new general procedure for carbon nanotube modification based on polyelectrolyte layer-by-layer assembly. We have built multilayer structures around individual carbon nanotube bridges by first modifying the nanotube surface with a pyrene derivative followed by layer-by-layer deposition of polyelectrolyte macroions on the nanotube. Transmission electron microscopy and scanning confocal fluorescence microscopy images confirm the formation of nanometer-thick amorphous polymer nanoshells around the nanotubes. These multilayer polyelectrolyte shells on individual carbon nanotubes introduce nearly unlimited opportunities for the incorporation of various functionalities into nanotube devices, which, in turn, opens up th...

176 citations

Journal ArticleDOI
TL;DR: A quantitative model is presented that shows how accumulation of the amorphous carbon patches at the catalyst particle surface and the carbon diffusion to the growing nanotube perimeter causes this abrupt growth cessation and the nonlinear behavior of the growth rate as a function of total process pressure.
Abstract: We have investigated growth kinetics of multiwall carbon nanotube (MWCNT) arrays produced by catalytic thermal decomposition of ethylene gas in hydrogen, water, and argon mixture. The MWCNT growth rate exhibits a nonmonotonic dependence on total pressure and reaches a maximum at ∼750 Torr of total pressure. Water concentrations in excess of 3000 ppm lead to the decrease in the observed growth rate. Optimal pressure and water concentration combination results in a reliable growth of well-aligned MWCNT arrays at a maximum growth rate of ∼30 μm/min. These MWCNT arrays can reach heights of up to 1 mm with typical standard deviations for the array height of less than 8% over a large number of process runs spread over the time of 8 months. Nanotube growth rate in this optimal growth region remains essentially constant until growth reaches an abrupt and irreversible termination. We present a quantitative model that shows how accumulation of the amorphous carbon patches at the catalyst particle surface and the ca...

110 citations

Journal ArticleDOI
TL;DR: Finite-element analysis from the structure of the labrynthine internal structure of a tantalum oxide nanofoam reveals mechanical properties consistent with bulk samples and with a diffusion-limited cluster aggregation model, while excess mass on the nodes discounts the dangling fragments hypothesis of percolation theory.
Abstract: Ultralow density polymers, metals, and ceramic nanofoams are valued for their high strength-to-weight ratio, high surface area, and insulating properties ascribed to their structural geometry. We obtain the labrynthine internal structure of a tantalum oxide nanofoam by x-ray diffractive imaging. Finite-element analysis from the structure reveals mechanical properties consistent with bulk samples and with a diffusion-limited cluster aggregation model, while excess mass on the nodes discounts the dangling fragments hypothesis of percolation theory.

107 citations

Journal ArticleDOI
TL;DR: It is demonstrated that complex interactions of adsorbed species with the device substrate and the surrounding electrolyte can produce significant and sometimes unexpected effects on the device characteristics.
Abstract: Carbon nanotube transistors are a promising platform for the next generation of nonoptical biosensors. However, the exact nature of the biomolecule interactions with nanotubes in these devices remains unknown, creating one of the major obstacles to their practical use. We assembled alternating layers of oppositely charged polyelectrolytes on the carbon nanotube transistors to mimic gating of these devices by charged molecules. The devices showed reproducible oscillations of the transistor threshold voltage depending on the polarity of the outer polymer layer in the multilayer film. This behavior shows excellent agreement with the predictions of a simple electrostatic model. Finally, we demonstrate that complex interactions of adsorbed species with the device substrate and the surrounding electrolyte can produce significant and sometimes unexpected effects on the device characteristics.

105 citations


Cited by
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Journal ArticleDOI
20 Mar 2008-Nature
TL;DR: Some of the science and technology being developed to improve the disinfection and decontamination of water, as well as efforts to increase water supplies through the safe re-use of wastewater and efficient desalination of sea and brackish water are highlighted.
Abstract: One of the most pervasive problems afflicting people throughout the world is inadequate access to clean water and sanitation. Problems with water are expected to grow worse in the coming decades, with water scarcity occurring globally, even in regions currently considered water-rich. Addressing these problems calls out for a tremendous amount of research to be conducted to identify robust new methods of purifying water at lower cost and with less energy, while at the same time minimizing the use of chemicals and impact on the environment. Here we highlight some of the science and technology being developed to improve the disinfection and decontamination of water, as well as efforts to increase water supplies through the safe re-use of wastewater and efficient desalination of sea and brackish water.

6,967 citations

Journal ArticleDOI
05 Aug 2011-Science
TL;DR: The possible reductions in energy demand by state-of-the-art seawater Desalination technologies, the potential role of advanced materials and innovative technologies in improving performance, and the sustainability of desalination as a technological solution to global water shortages are reviewed.
Abstract: In recent years, numerous large-scale seawater desalination plants have been built in water-stressed countries to augment available water resources, and construction of new desalination plants is expected to increase in the near future. Despite major advancements in desalination technologies, seawater desalination is still more energy intensive compared to conventional technologies for the treatment of fresh water. There are also concerns about the potential environmental impacts of large-scale seawater desalination plants. Here, we review the possible reductions in energy demand by state-of-the-art seawater desalination technologies, the potential role of advanced materials and innovative technologies in improving performance, and the sustainability of desalination as a technological solution to global water shortages.

4,840 citations

Journal ArticleDOI
01 Feb 2013-Science
TL;DR: Although not yet providing compelling mechanical strength or electrical or thermal conductivities for many applications, CNT yarns and sheets already have promising performance for applications including supercapacitors, actuators, and lightweight electromagnetic shields.
Abstract: Worldwide commercial interest in carbon nanotubes (CNTs) is reflected in a production capacity that presently exceeds several thousand tons per year. Currently, bulk CNT powders are incorporated in diverse commercial products ranging from rechargeable batteries, automotive parts, and sporting goods to boat hulls and water filters. Advances in CNT synthesis, purification, and chemical modification are enabling integration of CNTs in thin-film electronics and large-area coatings. Although not yet providing compelling mechanical strength or electrical or thermal conductivities for many applications, CNT yarns and sheets already have promising performance for applications including supercapacitors, actuators, and lightweight electromagnetic shields.

4,596 citations

Journal ArticleDOI
TL;DR: Department of Materials Science, University of Patras, Greece, Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, and Dipartimento di Scienze Farmaceutiche, Universita di Trieste, Piazzale Europa 1, 34127 Triesteadays.
Abstract: Department of Materials Science, University of Patras, 26504 Rio Patras, Greece, Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Avenue, 116 35 Athens, Greece, Institut de Biologie Moleculaire et Cellulaire, UPR9021 CNRS, Immunologie et Chimie Therapeutiques, 67084 Strasbourg, France, and Dipartimento di Scienze Farmaceutiche, Universita di Trieste, Piazzale Europa 1, 34127 Trieste, Italy

3,886 citations

Journal ArticleDOI
27 Jan 2012-Science
TL;DR: Submicrometer-thick membranes made from graphene oxide can be completely impermeable to liquids, vapors, and gases, including helium, but these membranes allow unimpeded permeation of water (H2O permeates through the membranes at least 1010 times faster than He).
Abstract: Permeation through nanometer pores is important in the design of materials for filtration and separation techniques and because of unusual fundamental behavior arising at the molecular scale. We found that submicrometer-thick membranes made from graphene oxide can be completely impermeable to liquids, vapors, and gases, including helium, but these membranes allow unimpeded permeation of water (H 2 O permeates through the membranes at least 10 10 times faster than He). We attribute these seemingly incompatible observations to a low-friction flow of a monolayer of water through two-dimensional capillaries formed by closely spaced graphene sheets. Diffusion of other molecules is blocked by reversible narrowing of the capillaries in low humidity and/or by their clogging with water.

2,602 citations