Under certain conditions, electrophoretic deposition (EPD) of single-wall carbon nanotubes (SWCNTs) onto metal at the base of nanoscale insulating windows can result in a single SWCNT per window, bonded at one end to the metal. During EPD charge, buildup on the insulator creates electrostatic lenses at the windows that control the trajectory of the SWCNTs. The aim is to develop a reproducible process for deposition of individual vertically oriented SWCNTs into each window to enable novel devices.
View Article and Find Full Text PDFA catalytic site typically consists of one or more atoms of a catalyst surface that arrange into a configuration offering a specific electronic structure for adsorbing or dissociating reactant molecules. The catalytic activity of adjacent bimetallic sites of metallic nanoparticles has been studied previously. An isolated bimetallic site supported on a non-metallic surface could exhibit a distinctly different catalytic performance owing to the cationic state of the singly dispersed bimetallic site and the minimized choices of binding configurations of a reactant molecule compared with continuously packed bimetallic sites.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2013
Highly dispersed molybdenum oxide supported on mesoporous silica SBA-15 has been prepared by anion exchange resulting in a series of catalysts with changing Mo densities (0.2-2.5 Mo atoms nm(-2) ).
View Article and Find Full Text PDFWater-gas shift (WGS) reactions on Co3O4 nanorods and Co3O4 nanorods anchoring singly dispersed Pt atoms were explored through building correlation of catalytic performance to surface chemistry of catalysts during catalysis using X-ray absorption spectroscopy, ambient pressure X-ray photoelectron spectroscopy (AP-XPS), and environmental TEM. The active phase of pure Co3O4 during WGS is nonstoichiometric cobalt monoxide with about 20% oxygen vacancies, CoO0.80.
View Article and Find Full Text PDFNanostructured chitosan (CS) and a chitosan-Zn based (Zn-CS) complex have been synthesized and simultaneously deposited on cotton fabrics using ultrasound. SEM measurements revealed that the coating consists of nanoparticles (NPs) of ca. 40 nm in diameter, homogeneously dispersed along the yarns.
View Article and Find Full Text PDFHere we present a carbon nanotube based device to noninvasively and quickly detect mobile single cells with the potential to maintain a high degree of spatial resolution. The device utilizes standard complementary metal oxide semiconductor (CMOS) technologies for fabrication, allowing it to be easily scalable (down to a few nanometers). Nanotubes are deposited using electrophoresis after fabrication in order to maintain CMOS compatibility.
View Article and Find Full Text PDFGd-doped CeO(2) exhibits an anomalously large electrostriction effect generating stress that can reach 500 MPa. In situ XANES measurements indicate that the stress develops in response to the rearrangement of cerium-oxygen vacancy pairs. This mechanism is fundamentally different from that of materials currently in use and suggests that Gd-doped ceria is a representative of a new family of high-performance electromechanical materials.
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