CdBi₂S₄‑Decorated Aminated Polyacrylonitrile Nanofiber for Photocatalytic Treatment of Cr(VI) and Tetracycline Wastewater

The significant threat posed by the high toxicity of heavy metals and antibiotics in water pollutants has prompted a growing emphasis on the development of highly efficient removal methods for these pollutants. In this paper, flexible electrospinning polyacrylonitrile (PAN) nanofiber-supported CdBi₂S₄ was synthesized via a hydrothermal method, followed by amination treatment with diethylenetriamine (DETA). The as-prepared CdBi₂S₄/NH₂–PAN nanofiber, enriched with sulfur vacancies, demonstrated outstanding visible-light trapping ability and a suitable band gap, leading to efficient separation and transport of photogenerated carriers, ultimately resulting in exceptional photocatalytic capability. The optimal 3-CdBi₂S₄/NH₂–PAN nanofiber achieved impressive reduction rates of 92.26% for Cr(VI) and 96.45% for tetracycline hydrochloride (TCH) within 120 min, which were much higher than those for CdS/NH₂–PAN, Bi₂S₃/NH₂–PAN, and CdBi₂S₄/PAN nanofibers. After five cycles, the removal rate of the CdBi₂S₄/NH₂–PAN nanofiber consistently remained above 90%. Their ease of separation and recovery from the application environment contributes to their practicality. Additionally, compared with conventional suspended particle catalyzers, the composite nanofiber exhibited remarkable flexibility and self-supporting properties.