Facet-Mediated Interfacial Zn–O _v –Ce Sites for Enhanced CO ₂ Electroreduction

High-dispersion Zn-based catalysts are promising candidates to replace noble-metal catalysts for the electrochemical CO₂ reduction reaction (CO₂RR). However, it is still challenging to identify and stabilize active Zn species to achieve high activity and selectivity. Herein, the Zn species are anchored on different crystal facets of CeO₂, and the interaction between Zn atoms and specific facets of CeO₂ for the CO₂RR is investigated. The Zn/CeO₂(110) catalyst, with CeO₂ nanorods exposing the (110) facet, exhibits a high Faradaic efficiency (FE) of 75.6% for CO production at -1.4 V vs RHE, which is 1.3 and 1.6 times higher than that of Zn/CeO₂(100) and Zn/CeO₂(111), respectively. The CO partial current density of Zn/CeO₂(110) achieves 3.89 mA·cm^-2 at -1.4 V vs RHE, superior to the other counterparts. Detailed characterizations reveal that the strong interactions between the CeO₂(110) facet and Zn atoms induce the generation of more oxygen vacancies. The asymmetric Zn-O_v-Ce sites facilitate the stabilization of Zn species with a small particle size. Moreover, the interfacial Zn-O_v-Ce sites and oxygen vacancies significantly promote CO₂ activation, thereby favoring subsequent *COOH formation and CO production. This study opens a new avenue to design efficient metal oxide catalysts by engineering specific facets and interfacial active sites.