Photocatalytic product-selective reduction of CO2, CO and carbonates

Abstract CO2 conversion to value-added chemicals is a crucial technology towards carbon-neutral fuels.1 Photocatalysis using sunlight is an energy-efficient alternative to electrochemical and thermal CO2 reduction.1 Photocatalysts usually yield either CO or HCO2H with varying degrees of selectivity.1 Herein, a lanthanide-based photocatalytic platform producing CO, HCO2H, CH4 or CH3OH is reported. The catalyst consists of a pendant amine for CO2 capture and a light-harvesting sensitiser that generates the reactive divalent lanthanide centre. CO2 reduction to CO or formate was possible with >99% selectivity and with the highest turnover number reported for a photocatalyst by virtue of a distinct mechanistic pathway. Attractive (bi)carbonate CO2 feedstocks were efficiently converted to CO, and CO could be reduced to the secondary products methane and methanol, demonstrating the wide utility of the platform.