Ag-decorated core-shell Sm2O3@TiO2 nanocomposites with enhanced visible-light photocatalytic performance

Ag-decorated core-shell Sm2O3@TiO2 (Ag-Sm@TiO2) nanocomposites were synthesized for the photocatalytic degradation of rhodamine B (RhB) under visible light irradiation. Compared with core-shell Sm2O3@TiO2 nanoparticles, the enhanced photocatalytic activity of Ag-Sm@TiO2 under visible light region was attributed to the surface plasmonic resonance effect of metallic silver and the interface effect between Sm2O3 and TiO2 in Fenton reaction system. The heterojunction consisted metallic Ag-0 nanoparticles, Sm2O3 core, and TiO2 shell was suitable for the separation of photoexcited electron-hole pairs and the suppression of charge carriers recombination. In addition, the center dot OH radical was the key active radicals for the photocatalytic degradation of RhB in visible light region. Removal efficiency of RhB over Ag-Sm@TiO2 increased and then decreased with the increasing Ag amount, of which the 6-Ag-Sm@TiO2 with metallic Ag-0 nanoparticles of 6.0 wt% exhibited the best photo catalytic activity and slightly deactivated after five cycle times.