In Situ Hard X-ray Photoelectron Study of O2 and H2O Adsorption on Pt Nanoparticles

详细信息    查看全文

• 作者：Yitao Cui ; Yoshihisa Harada ; Eiji Ikenaga ; Rui Li ; Naoki Nakamura ; Tatsuya Hatanaka ; Masaki Ando ; Toshihiko Yoshida ; Guo-Ling Li ; Masaharu Oshima
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：May 26, 2016
• 年：2016
• 卷：120
• 期：20
• 页码：10936-10940
• 全文大小：308K
• 年卷期：0
• ISSN：1932-7455

文摘

To improve the efficiency of Pt-based cathode catalysts in polymer electrolyte fuel cells, understanding of the oxygen reduction process at surfaces and interfaces in the molecular level is essential. In this study, H₂O and O₂ adsorption and dissociation as the first step of the reduction process were investigated by in situ hard X-ray photoelectron spectroscopy (HAXPES). Pt 5d valence band and Pt 3d, Pt 4f core HAXPES spectra of Pt nanoparticles upon H₂O and O₂ adsorption revealed that H₂O adsorption has a negligible effect on the electronic structure of Pt, while O₂ adsorption has a significant effect, reflecting the weak and strong chemisorption of H₂O and O₂ on the Pt nanoparticle, respectively. Combined with ab initio theoretical calculations, it is concluded that Pt 5d states responsible for Pt–O₂ bonding reside within 2 eV from the Fermi level.