Visible-light driven room-temperature coupling of methane to ethane by atomically dispersed Au on WO_(3)

摘要

Gold(Au)as co-catalyst is remarkable for activating methane(CH4),especially atomically dispersed Au with maximized exposing active sites and specific electronic structure.Furthermore,singlet oxygen(^(1)O_(2))typically manifests a mild redox capacity with a high selectivity to attack organic substrates.Peroxomonosulfate(PMS)favors to produce oxidative species 102 during the photocatalytic reactions.Thus,combining atomic Au as co-catalyst and ^(1)O_(2) as oxidant is an effective strategy to selectively convert CH4.Herein,we synthesized atomically dispersed Au on WO_(3)(Au/WO_(3)),where Au was in the forms of single atoms and clusters.At room temperature,such Au/WO_(3) exhibited enhanced photocata lytic conversion of CH4 to CH3 CH3 with a selectivity,up to 94%,under visible light.The radicals-pathway mechanism of CH4 coupling has also been investigated through detection and trapping experiment of active species.Theoretical calculations further interpret the electronic structure of Au/WO_(3) and tip-enhanced local electric field at the Au sites for promoting CH4 conversion.