Syngas production from electrocatalytic CO₂ reduction with high energetic efficiency and current density

Abstract

The direct conversion of CO₂ to syngas with controllable composition remains an intense interest for the production of renewable fuels. Large current density and high cell voltage efficiency are critical from a practical viewpoint for electrochemical CO₂ reduction reaction (CRR), while the design of catalysts is a great challenge. Here, we report oxide-derived Cu nanowires with abundant, highly dispersed two-phase CuO heterostructures for syngas generation. The specified H₂/CO ratios of 1, 2 and 3, with extra high CRR faradic (90%) and energetic (50%) efficiencies, were achieved. Density functional theory calculations reveal that the misfit dislocation sites in the electrocatalyst break the inherent scaling relationship of CRR intermediates' adsorption energies with an extraordinarily strong adsorption of *COOH and consequently promote excellent activity of the catalyst toward CRR. Driven by a commercial solar cell (working voltage of 2.2 V) under direct sunlight, the freestanding electrocatalyst can steadily generate syngas of the desired composition using CO₂ as a feedstock.