Photo-thermal cooperation for the conversion of CO2 and CH4 with H2O to C2 oxygenates over SrTiOx supported CuCo

ABSTRACT Photosynthesis is a potential strategy to enable endergonic process that usually needs high-temperature in thermochemistry to supply the energy for inert-bond activation and/or strong endothermic reaction . The conversion of CO 2 into value-added C 2 -oxygenates is a promising process to realize artificial photosynthesis , but suffers from relatively lower efficiency due to complex multi-electron (≥ 10) transfer processes and sluggish kinetics of C–C coupling. This work proposes an all-new H 2 O-promoted strategy for efficient production of C 2 oxygenates from the concurrent activation and subsequent co-conversion of CO 2 with CH 4 under photo-thermal cooperation, in which photocatalytic H 2 O-splitting derived active hydrogen species for CO 2 activation, and concomitant active oxygen species for CH 4 activation. A formation rate of as high as 2.05 mmol g −1 h −1 for C 2 -oxygenates (CH 3 CHO and CH 3 CH 2 OH) in a selectivity of > 86% has been afforded over SrTiO x supported CuCo under 200 °C and ultraviolet-visible illumination. It has been revealed that SrTiO x drives photocatalytic H 2 O-splitting under the excitation primary from ultraviolet light, paired Cu I /Cu 0 sites promote the formation of *CH x O intermediate from CO 2 , Co sites conduct CH 4 -to-*CH 3 , and C–C coupling of *CH x O and *CH 3 on adjacent Cu-Co facilitates the generation of C 2 -oxygenates.