Synthesis of Co3O4/BiOBr/BiOI Ternary Heterostructure and its Photocatalytic Degradation of RhB

Rhodamine B (RhB), an alkaline cationic organic dye, poses a significant threat to natural water environments. In this investigation, composites of Co 3 O 4 and BiOBr/BiOI were synthesized and evaluated for degradation of RhB under visible light irradiation. The photocatalyst (CBB-2) with a 10wt% Co 3 O 4 composite exhibited superior degradation efficiency, achieving 99.5% within 80 min and maintaining robust stability over four cycles. Meanwhile, after 90 min of light exposure, the mineralization rate of RhB reached 57.23%. A suite of characterization techniques verified the successful synthesis of the dual type-II heterojunction in the composite catalyst and the reinforced interactions among its components, thereby enhancing charge separation efficiency and photoresponsive performance. Free radical quenching experiments elucidated the critical role of •O 2 - and h + as radicals in the photocatalytic reaction process.