Wetting induced oxidation of Pt-based nano catalysts revealed by
high energy resolution X-ray absorption spectroscopy
その場高分解能X線吸収分光によって明らかにした水蒸気によるプラチナ触媒の酸化促進
Cui, Y.-T.*; 原田 慈久*; 丹羽 秀治*; 畑中 達也*; 中村 直樹*; 安藤 雅樹*; 吉田 稔彦*; 石井 賢司*; 松村 大樹
; 陰地 宏*; 大渕 博宣*; 尾嶋 正治*
Cui, Y.-T.*; Harada, Yoshihisa*; Niwa, Hideharu*; Hatanaka, Tatsuya*; Nakamura, Naoki*; Ando, Masaki*; Yoshida, Toshihiko*; Ishii, Kenji*; Matsumura, Daiju; Oji, Hiroshi*; Ofuchi, Hironori*; Oshima, Masaharu*
In situ high energy resolution fluorescence detection X-ray absorption spectroscopy (HERFD-XAS) was used to systematically evaluate interactions of H
O and O
adsorbed on Pt and Pt
Co nanoparticle catalysts in different particle sizes. The systematic increase in oxidation due to adsorption of different species (H
O adsorption
O
adsorption
O
+ H
O coadsorption) suggests that cooperative behavior between O
and H
O 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 O
/H
O adsorption and their cooperative effect upon coadsorption are responsible for the specific activity of Pt catalysts.