Hefei National Research Center for Physical Sciences at the Microscale, School of Chemistry and Materials Science, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui230026, China.
Institute of Energy, Hefei Comprehensive National Science Center, Hefei, Anhui230031, China.
ACS Nano. 2023 Feb 14;17(3):2620-2628. doi: 10.1021/acsnano.2c10534. Epub 2023 Jan 30.
Pushing the performance limit of catalysts is a major goal of CO 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 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 clusters, determining an optimal configuration for CO electroreduction. The optimal catalyst achieves a maximum Faradaic efficiency (FE) of 67% and a maximum partial current density of -364 mA/cm for CH, and can maintain high CH FE values over 50% in a wide range of applied current densities (-50 ∼ -600 mA/cm), exceeding those of the reported catalysts.
推动催化剂性能极限是 CO 电催化向实际应用的主要目标。单原子催化剂被认为是实现这一目标的解决方案，但考虑到单原子位点的有限负载量和稳定性，这也是一把双刃剑。为了克服这一限制，应该很好地解决单原子在载体上的负载问题，这需要一个合适的模型系统。在此，我们报告了具有原子精确结构和高表面积与体积比的超小 CeO 团簇（2.4nm）的模型系统，用于负载 Cu 单原子。多种表征和理论计算的结合揭示了 Cu 单原子在 CeO 团簇上的负载位置和极限，确定了 CO 电催化的最佳配置。最佳催化剂的 CH 最大法拉第效率（FE）达到 67%，-364 mA/cm 的最大部分电流密度，并且可以在很宽的应用电流密度范围内（-50∼-600 mA/cm）保持超过 50%的高 CH FE 值，超过了报道的催化剂的值。
