Pushing the Performance Limit of Cu/CeO<sub>2</sub> Catalyst in CO<sub>2</sub> Electroreduction: A Cluster Model Study for Loading Single Atoms
Yawen Jiang, Keke Mao, Jiawei Li, Delong Duan, Jiayi Li, Xinyu Wang, Yuan Zhong, Chao Zhang, Hengjie Liu, Wanbing Gong, Ran Long, Yujie Xiong
Abstract
Pushing the performance limit of catalysts is a major goal of CO 2 electroreduction toward practical application. A single-atom catalyst is recognized as a solution for achieving this goal, which is, however, a double-edged sword considering the limited loading amount and stability of single-atom sites. To overcome the limit, the loading of single atoms on supports should be well addressed, requiring a suitable model system. Herein, we report the model system of an ultrasmall CeO 2 cluster (2.4 nm) with an atomic precise structure and a high surface-to-volume ratio for loading Cu single atoms. The combination of multiple characterizations and theoretical calculations reveals the loading location and limit of Cu single atoms on CeO 2 clusters, determining an optimal configuration for CO 2 electroreduction. The optimal catalyst achieves a maximum Faradaic efficiency (FE) of 67% and a maximum partial current density of −364 mA/cm 2 for CH 4, and can maintain high CH 4 FE values over 50% in a wide range of applied current densities (−50 ∼ −600 mA/cm 2 ), exceeding those of the reported catalysts.