Deciphering electronic metal-support interaction in Ce1/ZnO single-atom catalysts for boosting CO2 electroreduction

Single-atom catalysts (SACs) have triggered great interest in the field of catalysis due to their high atom utilization and unique structures. Tailoring the electronic metal-support interaction (EMSI) of SACs is crucial to enhancing the catalytic performance. Herein, a novel Ce 1 /ZnO SAC has been precisely constructed by a facile one-pot hydrothermal strategy, and the modulation of EMSI with different d-orbital electrons (Ce, Fe, and Zr) is for the first time proposed for electrochemical CO 2 reduction (CO 2 RR). The Ce 1 /ZnO catalyst exhibits an excellent performance with a Faradaic efficiency of 84% for CO production and a record-high turnover frequency of 10658 h -1 at -1.1 V vs. RHE, exceeding Zr 1 /ZnO and Fe 1 /ZnO counterparts. Detailed characterizations and theoretical calculations reveal that the EMSI effect induces charge redistribution via the asymmetric metal-O-Zn moieties, while the unique Ce 3+ /Ce 4+ redox feature can exert a more pronounced electronic communication with the substrate. The strong electronic interaction between single-atom Ce and ZnO alters the d-band center structure of Ce sites, facilitating the adsorption of CO 2 and lowering the energy barrier of *COOH formation, thus accelerating CO production. This work elucidates the pivotal role of the electronic metal-support communication effect in engineering SACs toward boosted catalysis. The electronic metal-support interaction (EMSI) of single-atom catalysts is demonstrated. The novel and low-cost Ce 1 /ZnO catalyst exhibits excellent performance, outperforming the Zr 1 /ZnO, Fe 1 /ZnO, and most of the reported SACs. The ZnO donates partial electrons to Ce via asymmetrical Ce-O-Zn moieties, significantly promoting the activation of CO 2 and the formation of *COOH, thus boosting the performance. • The novel and low-cost Ce 1 /ZnO single-atom catalyst is developed. • Electronic metal-support interaction (EMSI) in SACs is revealed. • Strong interaction between Ce 1 and ZnO alters the d-orbital center structure of Ce sites, achieving excellent CO 2 reduction performance. • The asymmetrical Ce-O-Zn moieties lower the energy barrier for *COOH formation, thus boosting CO 2 electroreduction.