Enhanced photocatalytic performance of BiVO4 for degradation of methylene blue under LED visible light irradiation assisted by peroxymonosulfate

Abstract

The enhancement of BiVO4 photocatalytic degradation of methylene blue (MB) through peroxymonosulfate (PMS) introduction was studied under LED light irradiation. The BiVO4 catalyst was prepared by the hydrothermal method, and its physicochemical properties were characterized through various surface means. The influencing factors on the MB decolorization, such as the PMS concentration, BiVO4 amount, initial solution pH value, and catalyst stability were determined. The results presented that the photocatalytic performance of BiVO4 for MB removal was effectively improved after adding the PMS in the photocatalysis system. Increasing BiVO4 and PMS dosages promoted the MB elimination, and the synergy process showed satisfactory MB decolorization effect from pH 4 to 10. Besides, the coupling system exhibited a good stability after the four recycles. Moreover, the reactive species were identified by radicals scavenging experiments, and the results displayed that the sulfate and hydroxyl radicals were in charge of the MB decomposition during this collaborative process.