Interfacial Synergy between the Cu Atomic Layer and CeO 2 Promotes CO Electrocoupling to Acetate.

Cu is considered to be an effective electrocatalyst in CO/CO ₂ reduction reactions (CORR/CO ₂ RR) because of its C-C coupling into C ₂₊ products, but it still remains a formidable challenge to rationally design Cu-based catalysts for highly selective CO/CO ₂ reduction to C ₂₊ liquid products such as acetate. We here demonstrate that spraying atomically layered Cu atoms onto CeO ₂ nanorods (Cu-CeO ₂ ) can lead to a catalyst with an enhanced acetate selectivity in CORR. Owing to the existence of oxygen vacancies (O _v ) in CeO ₂ , the layer of Cu atoms at interface coordinates with Ce atoms in the form of Cu-Ce (O _v ), as a result of strong interfacial synergy. The Cu-Ce (O _v ) significantly promotes the adsorption and dissociation of H ₂ O, 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-CeO ₂ reaches 1477 h ^-1 , surpassing that of Cu nanoparticle-decorated CeO ₂ nanorods, bare CeO ₂ 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.