Photodriven CO dimerization on Cu2O from an electronic-structure perspective

Abstract

Electrochemically driven CO₂ reduction into alcohols and hydrocarbons is a topic of intense study. Photocatalytic approaches, which instead are powered by light, are also reported, but these generally rely on two-component catalysts and yield only moderately reduced products with a single carbon atom. In this report, we use density functional theory, including its linear-response time-dependent implementation, to investigate the feasibility of photocatalytically driving the dimerization of CO chemisorbed on Cu₂O, a crucial step in the chemical conversion of CO₂ into C₂ products, such as ethanol and ethylene. We find that CO dimerization into OCCO is greatly aided by the photoinduced population of a low-lying LUMO that is bonding with respect to the C–C bond of two adjacently chemisorbed CO molecules.