Temperature difference effect induced self-assembly method for Ag/SBA-15 nanostructures and their catalytic properties for epoxidation of styrene

Abstract In this paper the first dynamics-controlled self-assembly method for Ag nanostructures in mesoporous channels is developed, and Ag/SBA-15 nanostructures are synthesized by a temperature difference effect induced self-assembly method with AgNO 3 as Ag precursor and SBA-15 as support. Different morphologies of Ag nanomaterials such as nanoparticles, nanorods, and nanowires can be controlled by changing the weight ratio of AgNO 3 /SBA-15. In the synthesis procedure, the temperature difference effect induces air volume shrinkage in the channel, and the drop in pressure pushes the molten AgNO 3 assembled into the channels step by step. Finally, Ag/SBA-15 nanostructures are obtained by calcination at 350 °C for 2 h. Furthermore, the catalytic activities of Ag/SBA-15 nanostructures toward the epoxidation of styrene are investigated, and Ag nanoparticles/SBA-15-130 shows 77.7% of conversion and 73.7% selectivity for the epoxidation of styrene.