Surface decoration of BiOBr with BiPO4 nanoparticles to build heterostructure photocatalysts with enhanced visible-light photocatalytic activity

BiPO 4 /BiOBr photocatalysts were successfully prepared via a facile in situ chemical transformation method. The X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV–vis diffuse reflection spectroscopy, X-ray photoelectron spectroscopy, photoluminescence and photocurrent measurements were employed to characterize the crystal structures, morphologies, optical properties, and electron-hole separation efficiency of as-synthesized photocatalysts. BiPO 4 /BiOBr composites exhibited much higher photocatalytic activity for the degradation of Rhodamine B than pure BiOBr under visible light irradiation. The significant enhancement of photocatalytic activity could be mainly ascribed to the formation of heterojunction structure of BiPO 4 /BiOBr composite which can effectively improve electron–hole separation during photocatalytic process. Moreover, the effects of Cl − , SO 4 2− , NO 3 − and HCO 3 − anions on the photodegradation performance were investigated, and the as-synthesized BiPO 4 /BiOBr photocatalysts exhibit excellent photo-stability under visible light irradiation.