BiOBr/BiOF composites for efficient degradation of rhodamine B and nitrobenzene under visible light irradiation

BiOBr/BiOF (BF) composites were successfully synthesized via a facile one-step hydrothermal method for the first time. The structures, morphologies and photocatalytic performances of BF composites were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, UV–vis absorption spectroscopy, X-ray photoelectron spectroscopy, photoluminescence spectroscopy and electrochemical impedance spectroscopy respectively. The results show that the BF composites exhibit enhanced photocatalytic performances in the degradation of RhB and nitrobenzene with maximum degradation rates of 100% (25 min) and 94% (300 min) under visible light irradiation, respectively. The improved photocatalytic performance is mainly ascribed to the small crystalline size and the reduced electron-hole pair recombination with the presence of BiOF in the composites. Furthermore, the photodegradation mechanism was investigated and the h⁺ and [rad]OH radicals are suggested to be the main active species for photocatalytic degradation of RhB and nitrobenzene.