Preparation of BiOBrxCl1-x solid solution photocatalyst with oxygen vacancies for degradation of methyl orange under simulated sunlight

BiOBr_xCl_1-x solid solution with oxygen vacancies was synthesized using a simple one-step hydrothermal method. The sample was characterized using comprehensive characterization techniques, and the results showed that the solid solution material was successfully prepared. Adjusting the relative proportion of halogens in BiOBr_xCl_1-x solid solution has a significant impact on the morphology, optical properties, and photocatalytic activity of the sample, and oxygen vacancies are introduced into the material. The presence of oxygen vacancies improves the separation efficiency of charge carriers and facilitates the activation of oxygen molecules into superoxide radicals. Among them, BiOBr_0.2Cl_0.8 showed flower-like microspheres morphology and exhibited the best photocatalytic activity. After 30 min of dark adsorption and 1 h of simulated sunlight exposure, the removal rate of methyl orange (MO) was 92.5%, which was 2.38 times higher than that of pure BiOBr (38.9%) and 2.09 times higher than that of pure BiOCl (44.3%), respectively.