Platinum doped bismuth vanadate (Pt/BiVO4) for enhanced photocatalytic pollutant degradation using visible light irradiation

Due to favourable bandgap for visible light absorption and catalytic activity, mixed metal vanadate is a fascinating family of materials. This paper describes the sonicated assisted hydrothermal synthesis of platinum doped bismuth vanadate (Pt/BiVO4) semiconductor photocatalyst. The photocatalytic activity of Pt/BiVO4 was tested against the degradation of methylene blue (MB) under visible light irradiation. The hydrothermal approach was used to prepare BiVO4 photocatalysts, whereas the sonication method was used to make Pt/BiVO4 heterostructure photocatalysts. Owed to strong connectivity between BiVO4 and Pt co-catalysts, the produced Pt/BiVO4 photocatalysts were mechanically stable during the photodegradation test. The reason for improved photocatalytic response and the basic involved mechanisms is debated in detail. The use of Pt as a co-catalyst increased photocatalytic activity. The ideal Pt addition concentration was observed at 3.0 wt% Pt/BiVO4 photocatalyst which exhibited 100% degradation efficiency within 3 h for methylene blue dye owing to substantial specific surface area (14.92 m2/g), reduced optical energy band gap (1.99 eV), and effective separation of electron–hole pairs. Electrons from the conduction band of BiVO4 transpose to Pt surface, Pt causes a prolonged charges lifetime; in addition, these electrons take part in photocatalytic activity. The results indicated that the photocatalytic activities of Pt/BiVO4 were improved compared with the pure BiVO4. The EPR results show that reactive OH· plays the primary part in MB deterioration, whereas h+ and ·O2 play minor roles. In conclusion, this work opens a new horizon for maturing Pt-based favourable and reasonable co-catalyst for commercial purposes owing to efficient solar utilization, low-cost, facile, and environmental-friendly scheme for degradation of organic pollutants at the industrial level in the future.