Fabrication of a novel bifunctional material of BiOI/Ag3VO4 with high adsorption-photocatalysis for efficient treatment of dye wastewater

A novel bifunctional material with high adsorption-photocatalysis, BiOI/Ag3VO4 was successfully synthesized using a facile solvothermal method followed by the chemical precipitation. Among the heterogeneous materials, the 30 wt% BiOI/Ag3VO4 exhibited the optimal performance of adsorption-photocatalysis. The removal of 25 mg/L of basic fuchsin, malachite green and crystal violet over 30 wt% BiOI/Ag(3)Va(4) was about 97%, 92% and 85%, respectively, after the adsorption for 1 h and then visible-light degradation for 2 h. The investigations of adsorption kinetics and isotherm demonstrated that the adsorption process followed the pseudo-second-order kinetic model and the Freundlich adsorption isotherm, respectively. The sequence of work function calculated by first-principles using CASTEP code was Ag< BiOI which promoted efficient separation of electron-hole pairs resulting in greatly enhanced photoactivity of BiOI/Ag3VO4. (C) 2015 Elsevier B.V. All rights reserved.