The flower-like BiOCl/BiOBr with heterojunction prepared by co-precipitation method to enhance its photocatalytic performance

One-step co-precipitation method was used to prepare the flower-like BiOCl/BiOBr composite materials (BOBCs) with heterojunction structures, in which various amounts of BiOBr were used to adjust the band gap of BiOCl and thereby improve its photocatalytic activity. Based on photocatalytic performance experiments, BOBC2, in which the molar ratio of BiOCl to BiOBr is 1:0.75, exhibited the highest photodegradation efficiency (90.5%) to remove ofloxacin after 100 min illumination. The cyclic utilization performance of BOBC2 under the same conditions was tested by a cycle experiment. It was found that its photocatalytic activity remained at a high level after three cycles. The composition and microstructure of the material were analyzed by characterization techniques including XRD, FTIR, XPS, and SEM. The optical properties and the degradation process of the material were studied by DRS, PL, photocurrent, and active species trapping methods. The reasonable mechanism for photocatalytic degradation of ofloxacin was proposed.

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