A strategy to control grain boundary density and Cu+/Cu0 ratio of Cu-based catalysts for efficient electroreduction of CO2 to C2 products

Cu(OH)2/CuO nanocomposites-derived Cu2O/Cu were highly efficient for CO2 electroreduction to C2 products. The highest faradaic efficiency and current density could reach 64.5% and 26.2 mA cm-2, respectively. By changing calcination time, moderate grain boundary density and Cu+/Cu0 ratio in catalysts can be controlled, leading to large number of active sites and low interfacial charge transfer resistance.