Search

Your search keyword '"Bando, Y."' showing total 2,079 results
Start Over Author "Bando, Y."
2,079 results on '"Bando, Y."'

253. Electrochemical Properties of Pt Epitaxial Layers Formed on Pd (111) in Ultra-High Vacuum.

Author

Bando, Y., Takahashi, Y., Ueta, E., Todoroki, N., and Wadayama, T.

Subjects
ELECTROCHEMICAL research, ELECTROCATALYSIS, OXYGEN reduction, EPITAXIAL layers, SCANNING tunneling microscopy
Abstract

Electrocatalytic properties for oxygen reduction reaction (ORR) of Pt (111) epitaxial layers on a Pdf (111) substrate are investigated. Scanning tunneling microscopy images of the as-prepared 0.6-nm- and 1.2-nm-thick Pt(111) epitaxial layers on Pd (111) (Pt0.6nm/Pd(111) and Pt1.2nm/Pd(111)) revealed that the topmost surface has atomically flat, 50-100-nm-wide terraces. Remarkable current features due to hydrogen storage and emission by the P d (111) substrate dominated the cyclic voltammograms of Pt0.6nm/Pd(111) in the potential range of 0.15-0.4 V vs. a reversible hydrogen electrode. In contrast, the curve of Pt1.2nm/P d (111) exhibited a shrinkage in the hydrogen charges (QH) in the potential range of 0.25-0.4 V, accompanied by the emergence of symmetrical redox features at 15 mV on the positive potential side, relative to Pt (111) "butterfly" feature. Both Pto.6nm/Pd(l 11) and Ptl,2nm/Pd( 111) showed ca. four times higher ORR activity than clean Pt(111), although their hydrogen-related behaviors and activity changes during applying potential cycles were much different. The results suggest that shrinkage in QH and positive shift in the onset potential of hydroxyl species are common features of the CV of highly ORR-active well-defined Pt-M(l 11) bimetallic surfaces and that the activity enhancements and the structural stabilities fairly depend on the surface structure of the epitaxial Pt(111) lattice. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

254. Single-walled B-doped carbon, B/N-doped carbon and BN nanotubes synthesized from single-walled carbon nanotubes through a substitution reaction

Author

Golberg, D., Bando, Y., Han, W., Kurashima, K., Sato, T., Golberg, D., Bando, Y., Han, W., Kurashima, K., and Sato, T.

Abstract

Bundles of single-walled boron-doped carbon (BxC1-x), boron- and nitrogen-doped carbon (BxC1-x-yNy) and boron nitride (BN) nanotubes were prepared by thermal treatment of a mixture of boron trioxide and bundles of single-walled carbon nanotubes at 1523-1623 K in a nitrogen flow. The (BxC1-x+BxC1-x-yNy)/BN nanotube yield ratio increased with decreasing temperature in the reaction zone. The nanotubes were characterised by using high-resolution transmission electron microscopy and electron energy loss spectroscopy. The diameter of the individual nanotubes in the resultant bundles was 1.2-1.4 nm, which was similar to the diameter of the starting C-nanotubes. The B/C ratio of the B-doped carbon nanotubes was of ≤0.1, whereas the BN nanotubes exhibited a B/N stoichiometry of ~1.0.

Published
1999

255. Fullerine and onion formation under electron irradiation of boron-doped graphite

Author

Golberg, D., Bando, Y., Kurashima, K., Sasaki, T., Golberg, D., Bando, Y., Kurashima, K., and Sasaki, T.

Abstract

The formation of single- and multi-shelled fullerene-type cages and onion-like nanoscale structures has been achieved in situ during electron irradiation of graphitic BxC1-x (x≤0.2) in a high resolution electron microscope. Once formed, the curled and closed structures were found to be quite stable to irradiation-induced damage. The B/C ratio was typically in the range of 0.02-0.10, as confirmed by electron energy loss spectroscopy using a 0.5 nm diameter electron probe. Unlike the quasi-spherical fullerene shape observed in pure carbon, the 2-D images of the boron-doped smaller fullerene-type cages resembled hexagons, and those of the larger curled objects revealed a polyhedral faceted shape suggestive of B-induced buckling of C-based curled structures. Similar to pure carbon onions, a dramatic shell spacing reduction for innermost layers compared to outermost layers was found in the B-doped multi-shelled curled and closed structures, indicating the possibility of B-doped diamond formation in the cores. The fullerene and onion morphology and some aspects of their formation and stability are discussed.

Published
1999

256. Atomic resolution of single-walled carbon nanotubes using a field emission high-resolution transmission electron microscope

Author

Golberg, D., Bando, Y., Bourgeois, L., Kurashima, K., Golberg, D., Bando, Y., Bourgeois, L., and Kurashima, K.

Abstract

High-resolution transmission electron microscopy (HRTEM) observations were carried out on the untreated C single-walled carbon nanotube (SWNT) produced under laser vaporization technique. Micrographs were taken at room temperature at a magnification of 4 × 505 on a negative film. The set of images were taken for each particular isolated tube or a SWNT bundle at the vicinity of the optimal defocus value of the microscope. The results provide the first experimental evidence of achieving atomic resolution of an individual C SWNT by means of HRTEM with a field emission gun.

Published
1999

290. Production and Characterization of Single-Crystal FeCo Nanowires Inside Carbon Nanotubes

Author

Elías, A. L., primary, Rodríguez-Manzo, J. A., additional, McCartney, M. R., additional, Golberg, D., additional, Zamudio, A., additional, Baltazar, S. E., additional, López-Urías, F., additional, Muñoz-Sandoval, E., additional, Gu, L., additional, Tang, C. C., additional, Smith, D. J., additional, Bando, Y., additional, Terrones, H., additional, and Terrones, M., additional

Published
2005
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results