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Title: Participation of hot electrons in oxygen adsorption and ethylene oxidation on metals

Abstract

This paper reports the results obtained in the course of generating hot electrons by a device that is easier to fabricate and has more stability to chemically active compounds that a metal-insulator-metal systems: a Shottky-barrier diode having planar contact between a metal and a donor-doped semiconductor. In order to elucidate the potential effect of the promotion of chemical transformation by hot electrons, two specimens of different barrier heights were used: one a silicon-gold contact, the second a gallium arsenide film coated with layers of silver and a InNi alloy (3% Ni). These contacts were used to measure the current-voltage curve, the peak intensities curves which were proportional to the quantities of oxygen, water and carbon dioxide employed, and the peak intensities proportional to the formation rates of ethylene oxidation products.

Authors:
; ;  [1]
  1. Russian Univ. of People`s Friendship, Moscow (Russian Federation)
Publication Date:
OSTI Identifier:
171928
Resource Type:
Journal Article
Resource Relation:
Journal Name: Doklady Physical Chemistry; Journal Volume: 341; Journal Issue: 4-6; Other Information: PBD: Apr 1995; TN: Translated from Doklady Akademii Nauk; 341: No. 4, 779-780(1995)
Country of Publication:
United States
Language:
English
Subject:
40 CHEMISTRY; TAIL ELECTRONS; PARTICLE PRODUCTION; HYDROCARBONS; OXIDATION; ADSORPTION; CHEMISORPTION; CATALYSTS

Citation Formats

Maganyuk, A.P., Starkovskii, N.I., and Yurchuk, S.Y. Participation of hot electrons in oxygen adsorption and ethylene oxidation on metals. United States: N. p., 1995. Web.
Maganyuk, A.P., Starkovskii, N.I., & Yurchuk, S.Y. Participation of hot electrons in oxygen adsorption and ethylene oxidation on metals. United States.
Maganyuk, A.P., Starkovskii, N.I., and Yurchuk, S.Y. 1995. "Participation of hot electrons in oxygen adsorption and ethylene oxidation on metals". United States. doi:.
@article{osti_171928,
title = {Participation of hot electrons in oxygen adsorption and ethylene oxidation on metals},
author = {Maganyuk, A.P. and Starkovskii, N.I. and Yurchuk, S.Y.},
abstractNote = {This paper reports the results obtained in the course of generating hot electrons by a device that is easier to fabricate and has more stability to chemically active compounds that a metal-insulator-metal systems: a Shottky-barrier diode having planar contact between a metal and a donor-doped semiconductor. In order to elucidate the potential effect of the promotion of chemical transformation by hot electrons, two specimens of different barrier heights were used: one a silicon-gold contact, the second a gallium arsenide film coated with layers of silver and a InNi alloy (3% Ni). These contacts were used to measure the current-voltage curve, the peak intensities curves which were proportional to the quantities of oxygen, water and carbon dioxide employed, and the peak intensities proportional to the formation rates of ethylene oxidation products.},
doi = {},
journal = {Doklady Physical Chemistry},
number = 4-6,
volume = 341,
place = {United States},
year = 1995,
month = 4
}
  • A study using solid-state detectors and mass spectrometry has been made of the formation and emission of oxygen atoms from the surface of silver, as well as of the reactivity of these species in the oxidation of ethylene. A comparison of the formation of the quasifree oxygen atoms and the steady-state reaction of the oxidation of ethylene allows them to conclude that oxygen atoms play an important role in this reaction.
  • Different adsorption sites for molecular and atomic oxygen on a silver surface and the epoxidation of ethylene have been studied by use of extended Hueckel calculations. Several types of adsorbed molecular oxygen on an Ag(110) surface have been considered, and end-on adsorption on top of silver, a peroxidic adsorbed molecular oxygen, either adsorbed on a silver atom on the surface or bound to one in the second layer, and finally molecular oxygen located in the grooves along the (110) and (001) directions. For atomic adsorbed oxygen four types of geometries have been considered.
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