Tuning the Interactions in CuO Nanosheet-Decorated CeO₂ Nanorods for Controlling the Electrochemical Reduction of CO₂ to Methane or Ethylene

Tuning metal–support interactions (MSIs) to precisely control the selectivity of supported Cu catalysts toward the CO2 reduction reaction (CO2RR) is a crucial yet challenging topic. Herein, a series of CuO nanosheet/CeO2 nanorod composites with various morphologies and compositions were synthesized and used as electrocatalysts. The CO2RR product distributions of composites are experimentally verified to be dependent on the loading amounts and sizes of CuO nanosheets, with the maximum Faradaic efficiency (FE) of CH4 and C2H4 reaching 37.8 and 44.8%, respectively. The mechanism investigation supports our perspective that modulating the strength of the MSIs between CuO nanosheets and CeO2 nanorods not only influences the adsorption properties of CO2RR intermediates but also further dominates the formation of exposed facets during the CuO structural reconstruction process, thus customizing the CO2RR pathway.