Plasmonic metallic Bi deposited Bi12SiO20 crystals with rich oxygen vacancies for enhanced photocatalytic degradation of RhB and 2,4-DCP

Metallic Bi coupled Bi12SiO20 (Bi/BSO) is synthesized by a solvothermal method. Characterization demonstrates the presence of Bi metal on Bi12SiO20, the intimate interface between Bi metal and Bi12SiO20, and the existence of oxygen vacancies in Bi/BSO. It possesses improved photocatalytic activity, and its reaction rates are 23 and 1.4 times higher than those of Bi12SiO20 in RhB and 2,4-DCP removal. Its enhanced photocatalytic activity is attributed to its enhanced visible-light-response and improved charge separation resulting from the surface plasmon resonance effect endowed by metallic Bi and the unique features of oxygen vacancies on Bi12SiO20. Meanwhile, with the addition of H2O2, its reaction rates are 3 times higher than that of Bi12SiO20 in 2, 4-DCP removal, indicating that oxygen vacancies are beneficial for the generation of (OH)-O-center dot. This work paves a new way to enhance the photocatalytic activity of Bi12SiO20 by utilizing the cost-effective plasmonic Bi metal and oxygen vacancies. (C) 2017 Elsevier Ltd. All rights reserved.