Facile fabrication of electrospun g-C3N4/Bi12O17Cl2/poly(acrylonitrile-co-maleic acid) heterojunction nanofibers for boosting visible-light catalytic ofloxacin degradation

Abstract

Developing excellent photocatalysts for pollutant degradation is of vital significance but still a big challenge. In this work, an electrospun g-C₃N₄/Bi₁₂O₁₇Cl₂/poly(acrylonitrile-co-maleic acid) (E-spun g-C₃N₄/Bi₁₂O₁₇Cl₂/PANCMA) nanofiber photocatalyst was fabricated by coaxial electrospinning of g-C₃N₄/Bi₁₂O₁₇Cl₂ and PANCMA and showed high adsorption capacity and excellent visible light catalytic degradation performance with the adsorption amount and degradation rate of antibiotic ofloxacin (OFL) as high as 4.44 mg g⁻¹ within 6 min and 94% within 20 min, respectively. Compared to pure g-C₃N₄ and Bi₁₂O₁₇Cl₂, the g-C₃N₄/Bi₁₂O₁₇Cl₂ heterojunction showed higher visible light absorption and degradation ability, ascribed to the synergistic effect of g-C₃N₄ and Bi₁₂O₁₇Cl₂ on the separation and utilization efficiency of photogenerated electron–hole pairs. E-spun g-C₃N₄/Bi₁₂O₁₇Cl₂/PANCMA nanofibers exhibited highly efficient photocatalytic activity over a wide pH range of 4.0–8.0 and some interference of metal ions and inorganic anions, and the reactive species including holes (h⁺), superoxide radicals , and hydroxyl radicals (˙OH) all participated in the photocatalytic degradation of OFL. Moreover, the E-spun g-C₃N₄/Bi₁₂O₁₇Cl₂/PANCMA possessed excellent cycling stability of 81.9% efficiency retention after fifteen consecutive tests. In addition, the possible degradation mechanism, intermediate products and degradation pathways of OFL were investigated by ESR tests, radical scavenger experiments, and LC-MS analysis. This study developed a feasible exemplificative strategy for fabricating new highly efficient and reusable photocatalyst candidate materials to remove environmental pollutants.