Highly Selective Photoelectroreduction of Carbon Dioxide to Ethanol over Graphene/Silicon Carbide Composites

Abstract Using sunlight to produce valuable chemicals and fuels from carbon dioxide (CO 2 ), i.e., artificial photosynthesis (AP) is a promising strategy to achieve solar energy storage and a negative carbon cycle. However, selective synthesis of C 2 compounds with a high CO 2 conversion rate remains challenging for current AP technologies. We performed CO 2 photoelectroreduction over a graphene/silicon carbide (SiC) catalyst under simulated solar irradiation with ethanol (C 2 H 5 OH) selectivity of>99 % and a CO 2 conversion rate of up to 17.1 mmol g cat −1 h −1 with sustained performance. Experimental and theoretical investigations indicated an optimal interfacial layer to facilitate the transfer of photogenerated electrons from the SiC substrate to the few‐layer graphene overlayer, which also favored an efficient CO 2 to C 2 H 5 OH conversion pathway.