Surface/interface reconstruction in-situ on Cu2O catalysts with high exponential facets toward enhanced electrocatalysis CO2 reduction to C2+products

Converting CO2 to value-added chemicals and fuels by the electrocatalytic reduction reaction (CO2RR) is a promising strategy for reducing CO2 emissions and achieving clean energy storage. Herein, Cu2O catalysts with various morphologies (hexapod concave rhombic dodecahedrons microcrystals enclosed with (331), (1 1 1) and (100) facets (D-Cu2O), cubic microcrystals enclosed with (100) facet (C-Cu2O) and octahedron microcrystals with (1 1 1) and (100) facets (O-Cu2O)) are prepared via the wet chemical reduction method. The in-situ for-mation of D-Cu2O/Cu, C-Cu2O/Cu and O-Cu2O/Cu surface/interface and the conversion mechanism of CO2 to C2+ products have been systematically studied. The electrocatalytic performance of D-Cu2O/Cu for CO2 to form C2+ products is superior to that of C-Cu2O/Cu and O-Cu2O/Cu, which the Faraday efficiencies (FE) of C2+ products (ethylene and ethanol) reaches 70 %. The experimental results combined in-situ Raman spectroscopy and density function theory (DFT) calculations demonstrate that the good electrochemical performance is relate to the surface reconstruction and facet interface, which provides a positive local electronic environment to enhance the adsorption of *CO intermediates and reduces the energy barrier for the activation the C-C coupling. This study will provide a new approach to improve the selectivity of CO2RR by interface engineering and surface.