Construction of BiVO4/CdS Z-type heterojunction for sunlight-driven degradation of quinolone antibiotics

Antibiotics are crucial medications for preventing and treating bacterial infections. However, due to their inherent resistance to degradation, they are also a major component of water pollutants. Semiconductor photocatalysis is considered to be an important green technology for sewage treatment. In this study, BiVO₄/CdS Z-type heterojunction was synthesized and applied in the photocatalytic degradation of tetracycline hydrochloride (TCH). The Z-type heterojunction not only facilitates the separation of photogenerated charges, but also preserves photogenerated electrons with strong reduction capability and photogenerated holes with high oxidation capability. Following visible light irradiation for 90 min, the efficiency of BiVO₄/CdS photocatalytic degradation of TCH reached 93.1%. Moreover, BiVO₄/CdS demonstrates notable degradation efficacy toward other quinolone antibiotics. Free radical trapping experiments and EPR test results suggest that superoxide radicals, hydroxyl radicals, photogenerated electrons, and holes serve as the primary active species in the photocatalytic degradation process of tetracycline hydrochloride. This study offers valuable insights into the development of Z-type heterojunction photocatalysts for the efficient degradation of tetracycline hydrochloride.

Graphical abstract