Performance Study on Photocatalytic Degradation of Tetracycline by BiOBr/ Mo 1‐x S 2 Composites

ABSTRACT This study successfully constructed a 3D hierarchical BiOBr/Mo 1−x S 2 Type II heterojunction photocatalyst via a solvothermal in situ precipitation coupled strategy, which significantly enhanced the visible‐light photocatalytic degradation performance for tetracycline (TC). The results demonstrate that the composite system achieved a 90% TC removal rate within 60 min under visible‐light irradiation, exhibiting markedly enhanced catalytic activity compared to pure BiOBr and Mo 1−x S 2 . Structural characterization revealed that wrinkled Mo 1 −xS 2 nanosheets were precisely anchored onto the surface of flower‐like BiOBr microspheres through interfacial chemical bonds, forming an intimately coupled heterointerface. This effectively broadened the visible‐light absorption range and optimized carrier dynamics. Photoluminescence spectroscopy and photocurrent response tests confirmed that the Type II band alignment mechanism significantly promoted the spatial separation and transport efficiency of photogenerated carriers. Active species trapping experiments indicated that h + holes played a predominant role in TC degradation, while the synergistically enhanced reactive oxygen species (ROS) production further accelerated pollutant oxidation. Moreover, the catalyst maintained 79.7% degradation efficiency after 5 cycles, demonstrating excellent stability and engineering application potential. This work provides new insights for designing efficient and stable heterojunction photocatalysts and lays an experimental foundation for practical wastewater treatment in complex systems.