Optimized design of novel Pt decorated 3D BiOBr flower-microsphere synthesis for highly efficient photocatalytic properties

Abstract

3D BiOBr flower-microspheres decorated with small amount (0.02–0.5 wt%) of Pt nanoparticles were successfully prepared via new electrostatic-adsorption-assisted light-reduction route. The as-prepared samples were characterized by XRD, SEM, HRTEM, EDS, XPS, UV–Vis DRS, PL, and photocurrent measurements. The photocatalytic activities were tested through the photocatalytic degradation of Bisphenol A (BPA) under visible light (420 nm < λ < 680 nm) and simulated sunlight (320 nm < λ < 680 nm) irradiation. The results indicate that Pt loading do not change the structural morphologies and particle sizes of BiOBr flower-microspheres, but there exists an enhanced photocurrent effect, greatly achieving the highly efficient photocatalytic activity of BiOBr under visible-light and simulated sunlight irradiation. 0.2 wt% Pt/BiOBr sample reveals the highest photocatalytic activity for the degradation on BPA with almost 92% under 10 min, much better than pure BiOBr and (P25) TiO2. The presence of synergistic effect between Pt4+ and Pt0 has vital impact on the electron capture and transfer from the semiconductor to noble metal, preventing the fast electron/hole recombination and participating in the multi-electron reduction of O2, and, consequently, achieving the formation of effective photocatalytic active species. Our findings should provide the fundamental data for making further research efforts in the hot topic on the monatomic Pt-modified photocatalyst systems.