Enhanced electroreduction of CO2 to C2+ products on heterostructured Cu/oxide electrodes

Summary

Electrochemical reduction of CO₂ to value-added multicarbon products has been limited by the inefficiency of the C–C coupling process on Cu. Coupling metal oxides with Cu surfaces offers new freedom to break scaling relationships, thus regulating the product distribution on Cu. Herein, we show that metal oxides with the capability to stabilize the adsorbed CO₂∗/CO∗ and decrease the Gibbs free energies of the C–C coupling process can promote the formation of C₂₊ products on oxide-modified Cu electrodes. As a representative, ZrO₂-modified Cu (Cu/ZrO₂) electrode shows a high faradic efficiency of 85% for C₂₊ products. In situ surface-enhanced Raman spectra confirm the enhanced adsorption of CO∗ on the Cu/ZrO₂ electrode, while theoretical calculations reveal the decreased energy barriers of the C–C coupling process at the Cu-ZrO₂ interfacial boundaries. This study sheds light on the structure-property relationship of metal-oxide heterostructured electrocatalysts and accelerates the implementation of CO₂ electroreduction toward high-value products.