Construction of binary BiVO4/g-C3N4 photocatalyst and their photocatalytic performance for reactive blue 19 reduction from aqueous solution coupling with H2O2

Abstract

A highly efficient binary composite consisting of ripple-like sheet g-C3N4 doped with paramecium-shape BiVO4 has been successfully fabricated in a mild method and was further characterized by X-ray diffraction, Transmission electron microscopy, Fourier-transform infrared spectroscopy, UV–Vis diffuse reflectance spectrum, and photoluminescence. Their photocatalytic performances were estimated by monitoring the degradation process of reactive blue 19 (RB19) in the aqueous phase under visible light irradiation. The results showed that when the mass ratio of BiVO4 and g-C3N4 was 1:5, the binary composite presented the best catalytic activities during the photocatalytic degradation of RB19, and the synthesized composite with H2O2 addition could further promote the photocatalytic activities. It is worth mentioning that H2O2 acted only as a electron acceptor for accelerating the separation of electron–hole pairs. The trapping experiments showed that ·O2− was main active species in photocatalytic degradation of RB19. The improving of photocatalytic performance can be put down to the synergistic effect of g-C3N4, BiVO4, and H2O2 in Z-scheme mechanism, which give rise to enlarge optical absorption range and suppress the recombination of photo-generated charge carrier.