Experimental study demonstrates direct photocatalytic conversion of methane to acetone over titania-supported palladium clusters, suggesting a route for natural gas upgrading.
Key Points
To achieve direct photocatalytic oxidative coupling of methane into acetone as a value-added liquid oxygenate under ambient conditions.
Synthesized titanium dioxide-supported palladium clusters (Pdc/TiO2) to facilitate charge separation.
Conducted photocatalytic methane conversion experiments under light irradiation at ambient conditions using methane as the sole carbon source.
Investigated reaction mechanisms and pathways via in situ spectroscopic techniques and theoretical calculations.
Pdc/TiO2 catalyzed an acetone yield of 20.7 ± 1.1 μmol·g⁻¹·h⁻¹ with a liquid-phase selectivity of 59.7% under light irradiation.
Electronic metal-support interactions between palladium clusters and TiO2 improved photogenerated charge carrier separation, driving water oxidation to generate hydroxyl radicals.
Spectroscopic and computational data revealed a hydroxyl-radical-mediated activation and carbon-carbon coupling mechanism.