Bismuth Oxyhydroxide-Pt Inverse Interface for Enhanced Methanol Electrooxidation Performance
Xuchun Wang,#,1 Miao Xie,#,1 Fenglei Lyu,*,1 Yun-Mui Yiu,2 Zhiqiang Wang,2 Jiatang Chen,2 Lo-Yueh Chang,1
Yujian Xia,1 Qixuan Zhong,1 Mingyu Chu,1 Hao Yang,1 Tao Cheng,*,1 Tsun-Kong Sham,*,2 and Qiao Zhang,*,1
1Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, 215123 Suzhou, China
2Department of Chemistry, University of Western Ontario, London, Ontario N6A5B7, Canada
Developing efficient Pt-based electrocatalysts for the methanol oxidation reaction (MOR) is of pivotal importance for large-scale application of direct methanol fuel cells (DMFCs), but Pt suffers from severe deactivation brought by the carbonaceous intermediates such as CO. Here, we demonstrate the formation of a bismuth oxyhydroxide (BiOx(OH)y)-Pt inverse interface via electrochemical reconstruction for enhanced methanol oxidation. By combining density functional theory calculations, X-ray absorption spectroscopy, ambient pressure X-ray photoelectron spectroscopy, and electrochemical characterizations, we reveal that the BiOx (OH)y-Pt inverse interface can induce the electron deficiency of neighboring Pt; this would result in weakened CO adsorption and strengthened OH adsorption, thereby facilitating the removal of the poisonous intermediates and ensuring the high activity and good stability of Pt2Bi sample. This work provides a comprehensive understanding of the inverse interface structure and deep insight into the active sites for MOR, offering great opportunities for rational fabrication of efficient electrocatalysts for DMFCs.