Electron-rich Pt active sites enable efficient complete dehydrogenation electrooxidation of formic acid on Pt/Ag@Bi 2 Te 3 triple-phase heterointerfaces

Abstract Realizing the dehydrogenation direct pathway of formic acid electrooxidation reaction (FAOR) via sequential dehydrogenation steps is crucial for direct formic acid proton exchange membrane fuel cells (DFAPEMFCs). Herein, a two-dimensional porous Pt/Ag@Bi2Te3 electrocatalyst featuring a triple-phase heterointerface is prepared via a visible light-induced strategy. The heterointerface effect and metal–support effect endow the Pt active sites with local electron-rich properties, thereby facilitating attack on the H atom of H–COO–H to cleave the C–H and O–H bonds and realize the direct pathway. The Pt/Ag@Bi2Te3 demonstrates remarkable FAOR mass and specific activities of 10.7 A·mgPt–1 and 45.46 mA·cm–2, outperforming commercial Pt/C by factors of 21.8 and 11.4, respectively. In the practical DFAPEMFC device, the Pt/Ag@Bi2Te3 delivers a peak power density of 116.2 mW·cm–2, indicating its application potential. Density functional theory calculations further confirm the electron-rich Pt active sites and higher energy efficiency for the complete dehydrogenation direct pathway. This study provides a new strategy for preparing highly efficient FAOR catalysts for actual DFAPEMFCs.