In situ Synthesis of Ultrasmall Au Clusters on Thiol-modified CeO2 with Enhanced Stability and CO Oxidation Activity

G old(Au) nanoclusters supported on various supports have been widely used in the fields of energy and catalysis. However, the poor thermal stability of Au nanoclusters on the support interface usually leads to a reduction or even loss of catalytic activity. Herein, we used an in situ reduction method to synthesize Au nanoclusters on ceria(CeO 2 ) carriers. In this method, sulfhydryl groups were used to modify CeO 2 nanospheres first, and then Au clusters with an average diameter of 1.5 nm were grown on the surface of ceria reduced with sodium borohydride. The presence of the Au-S-Ce structure enhances the electron transfer efficiency, making the material exhibit high CO oxidation activity at room temperature. Furthermore, due to the strong binding energy of S and Au, the material exhibits a high stability for long time running process. This strategy provides an idea for designing stable and active supported ultrasmall Au nanoclusters catalytic materials.