Interfacial Synergy between the Cu Atomic Layer and CeO2 Promotes CO Electrocoupling to Acetate

Cu is considered to be an effective electrocatalyst in CO/CO2 reduction reactions (CORR/CO2RR) because of its C-C coupling into C2+ products, but it still remains a formidable challenge to rationally design Cu-based catalysts for highly selective CO/CO2 reduction to C2+ liquid products such as acetate. We here demonstrate that spraying atomically layered Cu atoms onto CeO2 nanorods (Cu-CeO2) can lead to a catalyst with an enhanced acetate selectivity in CORR. Owing to the existence of oxygen vacancies (Ov) in CeO2, the layer of Cu atoms at interface coordinates with Ce atoms in the form of Cu- Ce (Ov), as a result of strong interfacial synergy. The Cu-Ce (Ov) significantly promotes the adsorption and dissociation of H2O, which further couples with CO to selectively produce acetate as the dominant liquid product. In the current density range of 50-150 mA cm-2, the Faradaic efficiencies (FEs) of acetate are over 50% with a maximum value of 62.4%. In particular, the turnover frequency of Cu-CeO2 reaches 1477 h-1, surpassing that of Cu nanoparticle-decorated CeO2 nanorods, bare CeO2 nanorods, as well as other existing Cu-based catalysts. This work advances the rational design of high-performance catalysts for CORR to highly value-added products, which may attract great interests in diverse fields including materials science, chemistry, and catalysis.