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Wetting Induced Oxidation of Pt-based Nano Catalysts Revealed by In Situ High Energy Resolution X-ray Absorption Spectroscopy.

ABSTRACT: In situ high energy resolution fluorescence detection X-ray absorption spectroscopy (HERFD-XAS) was used to systematically evaluate interactions of H₂O and O₂ adsorbed on Pt and Pt₃Co nanoparticle catalysts in different particle sizes. The systematic increase in oxidation due to adsorption of different species (H₂O adsorption 2 adsorption 2 + H₂O coadsorption) suggests that cooperative behavior between O₂ and H₂O adsorptions is responsible for the overpotential induced by hydrated species in fuel cells. From the alloying and particle size effects, it is found that both strength of O₂/H₂O adsorption and their cooperative effect upon coadsorption are responsible for the specific activity of Pt catalysts.

SUBMITTER: Cui YT

PROVIDER: S-EPMC5431092 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Wetting Induced Oxidation of Pt-based Nano Catalysts Revealed by In Situ High Energy Resolution X-ray Absorption Spectroscopy.

Cui Yi-Tao YT Harada Yoshihisa Y Niwa Hideharu H Hatanaka Tatsuya T Nakamura Naoki N Ando Masaki M Yoshida Toshihiko T Ishii Kenji K Matsumura Daiju D Oji Hiroshi H Ofuchi Hironori H Oshima Masaharu M

Scientific reports 20170503 1

In situ high energy resolution fluorescence detection X-ray absorption spectroscopy (HERFD-XAS) was used to systematically evaluate interactions of H2O and O2 adsorbed on Pt and Pt3Co nanoparticle catalysts in different particle sizes. The systematic increase in oxidation due to adsorption of different species (H2O adsorption <O2 adsorption <O2 + H2O coadsorption) suggests that cooperative behavior between O2 ...[more]

PMID: 28469163

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