Photocatalytic dehydrogenation of formic acid promoted by a superior PdAg@g-C3N4 Mott–Schottky heterojunction

Abstract

Herein, we report the production of a superior Mott–Schottky heterojunction that is based on PdAg nanowires (NWs) that grow in situ on graphitic carbon nitride (g-C₃N₄). Due to the strong Mott–Schottky effect between PdAg NWs and g-C₃N₄, the heterojunction enhances the photocatalytic dehydrogenation of formic acid (FA) (TOF = 420 h⁻¹) without additives and under visible light (λ > 400 nm) at 25 °C, which is the best value among all heterogeneous catalysts reported for the photocatalytic dehydrogenation of FA. The H₂ production rate is almost constant under the current reaction conditions. Detailed studies reveal that a favorable charge transfer from g-C₃N₄ and Ag to Pd makes Pd electron-rich, which enhances the catalytic activity and stability of the heterojunction for the photocatalytic dehydrogenation of FA under visible light. Our studies open up a new route to the design of a metal–semiconductor heterojunction for visible light-driven photocatalytic dehydrogenation of FA.