One-pot hydrothermal preparation of BiOBr/BiPO4 with improved photocatalytic performance originated from remarkably enhanced separation of electron-hole pairs.

In this paper, to further promote the photocatalytic performance of BiPO 4 , BiOBr was employed to couple with BiPO 4 . Rod-like BiOBr/BiPO 4 composites with improved photocatalytic performance were facilely constructed by one-pot hydrothermal method. The composites were characterized by Brunauer -Emmett-Teller (BET) method, X-ray diffraction patterns (XRD), UV–Vis diffuse reflectance spectra (DRS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), surface photovoltage spectroscopy (SPS) and electron spin-resonance (ESR) spectroscopy. The photocatalytic performance of the samples towards degradation of rhodamine B (RhB) and phenol aqueous solution was evaluated under the simulated sunlight irradiation. The SPS results reveal that the separation of photogenerated electron-hole pairs has been promoted due to the formation of heterojuctions. The ESR measurements demonstrate that OH and h + are involved in the photocatalytic reaction. The photocatalytic evaluation display that the sample with molar ratio of Br − /PO 4 3− = 0.4% holds the highest activity. The results further substantially exhibit that coupling BiPO 4 with BiOBr can remarkably boost the photocatalytic performance of BiPO 4 , benefiting from significantly enhanced separation of photoinduced charge pairs. Based on all the observations, a Z-scheme separation and transfer scheme of the photo-induced charge pairs of BiOBr/BiPO 4 was proposed. [ABSTRACT FROM AUTHOR]