A novel nano-sized BiOBr decorated K2La2Ti3O10 with enhanced photocatalytic properties under visible light

BiOBr-sensitized–K2La2Ti3O10 composite photocatalysts (BiOBr/K2La2Ti3O10) were fabricated by depositing BiOBr particles on the surface of K2La2Ti3O10 through a solvothermal method. The deposited BiOBr particles, with a uniform size of approximately 50 nm, were well dispersed on the surface of K2La2Ti3O10, and improved the visible light absorption of the composite material. The photocatalytic activities were evaluated by degrading Rhodamine B (RhB) under visible light irradiation. The BiOBr/K2La2Ti3O10 composites exhibited superior performance over pure BiOBr, and the deposition of BiOBr particles onto the host K2La2Ti3O10 significantly increased the photocatalytic decolorization ability of K2La2Ti3O10. An optimum loading of 45 wt% was found, and almost 95% of RhB could be degraded in 60 min under visible light irradiation using this preparation. Furthermore, the photocatalytic activity was stable in up to five consecutive runs. The enhancement in both photocatalytic activity and stability in the composites resulted from the closely contacted interfaces, which were beneficial for charge separation. The roles of the radical species were investigated, and the ·O2− and h+ were thought to dominate the photocatalytic process, while the ·OH was found to be relatively negligible. Based on the experimental results, a photocatalytic mechanism for organics degradation over BiOBr/K2La2Ti3O10 photocatalysts was proposed. - Graphical abstract: Photocatalytic reaction mechanisms of the as-prepared BiOBr/K2La2Ti3O10. - Highlights: • BiOBr particle modified K2La2Ti3O10 were successfully synthesized by solvothermal method. • BiOBr greatly increased visible light absorption for K2La2Ti3O10. • The photocatalyst exhibited high activities for organics degradation. • Mechanisms of charge separation in the BiOBr/K2La2Ti3O10 composites were proposed