Shape Effect of Atomically Precise Au25 Nanoclusters on Catalytic CO Oxidation

• Published in: Journal of physical chemistry. C 2022-10, Vol.126 (40), p.17114-17122
• Main Authors: Jin, Renxi, Liu, Xianchun, Zhao, Shuo, Xing, Yan, Jin, Rongchao
• Format: Article
• Language: English
• Subjects: C: Chemical and Catalytic Reactivity at Interfaces
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.2c06066

Understanding the catalytic behavior of metal nanoclusters at the atomic level remains a major dream in nanocatalysis research. Here, we study the catalytic behavior of two different Au25 nanoclusters (sphere vs rod) supported on TiO2 nanorods and obtain insights into the structure–property relationship for CO oxidation. The spherical [Au25(SCH2CH2Ph)18]− nanocluster exhibits a catalytic activity trend of volcano-shape with the increase of pretreatment temperature in oxygen from 150 to 300 °C. It is found that low-temperature pretreatment could make the cluster expose more active sites; hence, an increase in activity, while high-temperature pretreatment leads to a decrease in activity due to the thermally induced aggregation of clusters into larger particles. For the rod-shaped [Au25(PPh3)10(SCH2CH2Ph)5X2]2+ cluster, its activity decreases with the increase of pretreatment temperature from 150 to 300 °C. The different trends of spherical and rod-like Au25 catalysts are ascribed to their distinctly different atomic packing structures. This work demonstrates a control of the atomic structure of catalysts and the effects on the catalytic performance.