Well-defined gold nanoclusters with average size less than 2 nm have emerged as a new and novel catalyst. The gold nanocluster loaded on the oxide surface usually aggregates to larger particles at high temperature (...Well-defined gold nanoclusters with average size less than 2 nm have emerged as a new and novel catalyst. The gold nanocluster loaded on the oxide surface usually aggregates to larger particles at high temperature (〉 300℃), which is caused by the removal of the surface ligands. We herein pre-sent a novel method to prepare Au25cluster catalyst (-1.3 nm) with high thermal stability (up to 400℃). Au25@Si02 is synthesized via a co-hydrolyzing reaction of Au2s[SC3H6Si(OCH3)3118 and tet-raethyl orthosilicate, and then it is treated at different temperature (e.g., 200, 300, 400℃) in air to remove the organic ligands. Au25@SiO2 is well characterized by transmission electron microscopy, ultraviolet-visible spectroscopy and diffuse reflectance UV-vis spectroscopy. Further, the Au2s@SiO2 catalysts are investigated in the hydrogenation ofp-nitrophenol into p-aminophenol.展开更多
基金supported by the National Natural Science Foundation of China (21273231, 21422308)Dalian Excellent Youth Foundation (2014J11JH126) (FW)the Starting Funds of “Thousand Youth Talents Plan” (GL)~~
文摘Well-defined gold nanoclusters with average size less than 2 nm have emerged as a new and novel catalyst. The gold nanocluster loaded on the oxide surface usually aggregates to larger particles at high temperature (〉 300℃), which is caused by the removal of the surface ligands. We herein pre-sent a novel method to prepare Au25cluster catalyst (-1.3 nm) with high thermal stability (up to 400℃). Au25@Si02 is synthesized via a co-hydrolyzing reaction of Au2s[SC3H6Si(OCH3)3118 and tet-raethyl orthosilicate, and then it is treated at different temperature (e.g., 200, 300, 400℃) in air to remove the organic ligands. Au25@SiO2 is well characterized by transmission electron microscopy, ultraviolet-visible spectroscopy and diffuse reflectance UV-vis spectroscopy. Further, the Au2s@SiO2 catalysts are investigated in the hydrogenation ofp-nitrophenol into p-aminophenol.