Fabrication and efficient photocatalytic dye degradation over Z-scheme-based BiVO4/CdS heterojunction under visible-light irradiation

Abstract

Novel Z-scheme-based BiVO4/CdS photocatalysts with efficient charge separation were prepared by simple in situ hydrothermal method. The compact structure of the CdS nanorod and BiVO4 nanosheet has formed a Z-scheme heterojunction. The as-prepared BiVO4/CdS composites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, diffuse reflection spectroscopy, photoluminescence and photocurrent techniques. It was found that the BiVO4/CdS composites had the light-absorbing range and could efficiently degrade malachite green dye under visible-light irradiation. In this report, the result of the best degrading sample could achieve 92% in 30 min under visible light, respectively. BiVO4/CdS composites perform photocatalytic efficiently due to the Z-scheme. Furthermore, the Z-scheme-based BiVO4/CdS composites leaded to a major oxidation site at BiVO4, which successfully avoided photoetching of CdS during photocatalysis. Especially, the BiVO4/CdS system exhibits great photogenerated electron–hole pairs separation capabilities and high redox capabilities. This unique method of synthesizing Z-scheme-based BiVO4/CdS heterojunction has ability to reduce the cost and promote photocatalytic in visible-light range simultaneously.