The highly enhanced visible light photocatalytic degradation of gaseous o-dichlorobenzene through fabricating like-flowers BiPO4/BiOBr p-n heterojunction composites

In this paper, in order to enhance photo-induced electron-hole pairs separation of BiOBr, flowers-like BiPO4/BiPOBr p-n heterojunction composites was fabricated by a mixing in solvent method. The as prepared samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), IJV-vis absorption spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), and N-2 adsorption-desorption. Meanwhile, their photocatalytic properties were investigated by the degradation of gaseous o-dichlorobenzene under visible light irradiation. Due to its strong adsorption capacity and the formation of p-n heterojunction, compared with BiPO4 and BiOBr, the BiPO4/BiOBr composites showed higher photocatalytic activity in the degradation of gaseous o-DCB under visible light. Among them, 2% BiPO4/BiOBr showed the maximum value of the activity, whose degradation rate was about 2.6 times as great as the pure BiOBr. Furthermore, the OH center dot was confirmed the main active species during the photocatalytic process by the trapping experiments. The outstanding performance indicated that the photocatalysts could be applied to air purification for chlorinated volatile organic compound. (C) 2016 Elsevier B.V. All rights reserved.