Ultrasonic-assisted efficient degradation of tetracycline over ZnO/BiOBr heterojunctions: Synergistic effect and role of oxidative species

•ZnO/BiOBr heterojunction was applied to remove tetracycline.•0.2ZnO/BiOBr exhibited enhanced ultrasonic catalytic activity than that of BiOBr.•The modification of ZnO remarkably promoted charges separation efficiency of BiOBr.•The ⋅OH radicals are the dominant reactive species in tetracycline degradation.