Enhanced photodegradation activity of Rhodamine B by Co3O4/Ag3VO4 under visible light irriadiation

Highlights: ► Novel composite Co3O4/Ag3VO4 as catalyst. ► Higher activity for the photodegradation of RhB under visible light irradiation. ► Calcination temperature of catalyst has effect on photocatalytic activity. ► Catalyst electrodes demonstrate a rapid photocurrent response. - Abstract: Co3O4/Ag3VO4 composite photocatalysts were synthesized by the wetness impregnation method and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and diffuse reflectance spectroscopy (DRS). The photoactivity testing result shows that the Co3O4/Ag3VO4 composite exhibits enhanced photodegradation activity for Rhodamine B (RhB) under visible-light irradiation. The Co3O4 content and calcination temperature have a significant impact on the photocatalytic activities of the samples. The highest efficiency was observed on the 1.0 wt.% Co3O4/Ag3VO4 sample calcined at 653 K. Moreover, the photoelectrochemical performance with the method of transient photocurrent–time was investigated. Based on the results of the characterizations, the mechanism of enhanced photocatalytic activity is discussed.