CuO/ZnO/C electrocatalysts for CO2-to-C2+ products conversion with high yield: On the effect of geometric structure and composition

The comprehensive application of electrochemical CO2 conversion to multi-carbon hydrocarbons and oxygenates is limited by the low selectivity and activity of copper-derived catalysts. Here, we report co-precipitated CuO/ZnO/C catalysts directing cascade catalysis to enhance the yield of the C2+ products. The reduced ZnO nanoparticles supply extra CO to increase the *CO surface coverage on the reduced CuO nanoparticles, which boosts the C-C coupling reaction kinetics on the reduced CuO surface. The geometric arrangement and composition of phase-separated CuO and ZnO nanoparticles are two vital factors influencing the CO utilization efficiency. The optimum CuO/ZnO/C catalyst exhibits a maximum Faradic efficiency of 74.0 % for overall C2+ products and 50.9 % for C2H4 at -0.75 V vs. reversible hydrogen electrode, at which the total current density reaches 367 mA cm(-2).