Light‐driven oxidative coupling of methane to acetone over Pd clusters via • OH ‐mediated activation‐coupling route

Abstract

Direct oxidative coupling of methane to C 3 oxygenates represents a promising pathway for upgrading natural gas into value‐added chemicals, yet remains challenging due to the difficult CH activation and uncontrollable CC coupling process. Herein, we report the direct photocatalytic synthesis of acetone from CH 4 as the sole carbon source over TiO 2 ‐supported Pd clusters (Pd c /TiO 2 ) under ambient conditions. The electronic metal‐support interaction between Pd clusters and TiO 2 enhances the separation efficiency of photogenerated charge carriers in TiO 2 , thereby promoting water oxidation by photogenerated holes to generate abundant hydroxyl radicals. As a result, the Pd c /TiO 2 achieves an acetone yield of 20.7 ± 1.1 μmol·g −1 ·h −1 with a liquid‐phase acetone selectivity of 59.7% under light irradiation. Comprehensive in situ spectroscopic studies and theory calculations reveal a hydroxyl‐radical‐mediated activation‐coupling pathway on Pd c /TiO 2 . This work provides a new paradigm for precise carbon chain growth of CH 4 to value‐added liquid C 3 oxygenated compounds.