Synthesis, characterization, and testing of supported Au catalysts prepared from atomically-tailored Au38(SC12H25)24 clusters

摘要: Nearly monodispersed Au38(SC12H25)24 clusters (1.7 ± 0.2 nm) were synthesized using a modified Brust process while utilizing “thiol etching” approach for the ligand exchange. HRTEM, MALDI, FTIR, and XAS analysis confirmed formation of 38-atom in solution. This solution was used to impregnate microporous TiO2 support give 0.7% Au38/TiO2 catalyst. Subsequent drying air treatment with H2/He at 400 °C removed most sulfur ligands, also increased Au cluster size 3.9 0.96 nm. XPS EXAFS this supported catalyst showed trace levels residual sulfides, apparently located Au–TiO2 interface. CO oxidation tests on these show an activation energy range TOFs comparable those reported by others. These results suggest that controllable can be prepared thiol-ligated solution-based method, providing new synthesis catalysts.