Enhancing the photocatalytic activity of Bi₂MoO₆ by constructing tailored composites through a turnable amount of MoS₂

Ciprofloxacin (CIP, C₁₇H₁₈FN₃O₃), one of the main pollution sources detected in water, has raised intense issues. In order to resolve this issue, it is essential to achieve efficient degradation of CIP under visible light. Herein, a set of two-dimensional composites MoS₂/Bi₂MoO₆ were constructed, and proved via XRD, FT-IR, SEM, TEM, and XPS, respectively. In addition, the results recorded that when the optimized composites 0.5%-MoS₂/Bi₂MoO₆ were applied, the degradation rate of CIP was up to 91% at 120 min under the irradiation of visible light (> 395 nm) which was superior to that of the pure MoS₂ or Bi₂MoO₆. UV–Vis DRS, photocurrent, and electrical impedance analyses indicate that the outperformance of 0.5%-MoS₂/Bi₂MoO₆ is due to the optimized band gap and specific surface area. More importantly, a photocatalytic mechanism was proposed based on the analysis of GC–MS (according to the references (Dang et al. in Chem Eng J 422(15):130103, 2021; Zhu et al. in Environ Sci Pollut Res Int 30(11):28874–28888, 2022)) and active species. The result was manifest: CIP was degraded progressively under the attack of photocatalytically generated h⁺,^.O₂⁻. This work opens up a category for the construction of efficient Bi₂MoO₆-based composites and proposes a hypothetical mechanism and pathway for CIP degradation.