Reconstructed anti-poisoning surface for enhanced electrochemical CO2 reduction on Cu-incorporated ZnO

Zn-based materials are regarded as a family of promising electrocatalysts for electrochemical CO2 reduction reaction (e-CO2RR), especially for the CO2-to-CO conversion. However, their electrocatalytic performances should be improved and the conversion mechanism needs to be further studied. In this work, we fabricate Cu-incorporated ZnO (Cu25Zn-A) on Zn plate for e-CO2RR catalyst by a facile annealing method. We find that Cu25Zn-A achieves a high CO Faraday efficiency > 90% with a CO yield rate of 0.49 mmol cm−2 h−1. The improved catalytic activity on Cu25Zn-A is mainly attributed to the Cu steps on the reconstructed surface in the reaction: (1) that weakens the OH-/CO32- adsorption, leading to the anti-poisoning surface by preventing the formation of Zn hydroxide/carbonates; and (2) that enhances the adsorption/activation of reactants and stabilizes the intermediates. Additionally, the density of defects in Zn oxide is increased by the Cu-incorporation, resulting in improved deoxygenation step. Our findings may provide insightful understanding on the mechanism and guide the design of novel electrocatalyst for effective CO2 reduction.