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Indexed by:期刊论文

Date of Publication:2010-09-30

Journal:JOURNAL OF CATALYSIS

Included Journals:SCIE、EI、Scopus

Volume:275

Issue:1

Page Number:34-44

ISSN No.:0021-9517

Key Words:Methanol electro-oxidation; Electrocatalysis; Platinum catalyst; Hydrous ruthenium oxide; Catalyst promoter

Abstract:Pt-(RuO(x)H(y))(m) electrocatalysts (m being the atomic Ru/Pt ratio) supported on multi-walled carbon nanotubes, in which amorphous hydrous ruthenium oxide (RuO(x)H(y)) is the exclusive Ru-containing species, were prepared and comprehensively characterized by X-ray diffraction, X-ray photoelectron spectroscopy, temperature-programmed reduction, thermogravimetric analysis and transmission electron microscopy techniques. Cyclic voltammetry (CV) and chronoamperometry studies of CO stripping and methanol electro-oxidation indicated that the CO tolerance and catalytic activity of Pt improved remarkably by the co-presence of RuO(x)H(y). Repeated CV pretreatments in 0.5 M H(2)SO(4) up to potentials higher than 0.46 V (vs. SCE) induced significant dissolution of RuO(x)H(y), which changed the RuO(x)H(y) content, Pt-RuO(x)H(y) proximity and surface structure of Pt, and consequently altered the electrocatalytic activity of Pt in the final electrode. However, RuO(x)H(y) dissolution was not identified when the pretreatment potentials was set no higher than 0.46 V. Discussion on the promotional function of RuO(x)H(y) was made based on the peculiarity of RuO(x)H(y) as a mixed electron/proton conductor. (C) 2010 Elsevier Inc. All rights reserved.