Assembling g-C3N4 nanosheets on rod-like CoFe2O4 nanocrystals to boost photocatalytic degradation of ciprofloxacin with peroxymonosulfate activation

Water pollution caused by organic pollutants seriously threatens the ecological balance. Photocatalytic oxidation technology with green, environment-friendly characteristics can effectively dispose of organic pollutants in water, is the potential replacement of the traditional sewage treatment technology. In this work, CoFe2O4/g-C3N4 heterojunction with nanosheets-on microrods structure was designed and prepared by a simple solvothermal-calcination synthetic method, which was applied for the degradation of cyprofloxacin (CIP) through the com-bination of peroxymonosulfate (PMS) and photocatalysis. The results reveal that the optimal photocatalytic degradation efficiency of CIP (20 mg/L) in the prepared CoFe2O4/g-C3N4-10/PMS system reached 97% within 60 min, and the degradation rate at a high level during the four cycles. The effects of different environmental factors (catalyst dose, PMS dose and initial CIP concentration) on the degradation of the system were studied. The enhancement of photocatalytic activity in the CoFe2O4/g-C3N4 composite can be mainly attributed to accelerated separation and transfer of electrons and holes through the formation of heterojunctions, which is beneficial to stimulate PMS to produce more SO4 center dot- and center dot OH.

Automated summary

This study developed a novel CoFe2O4/g-C3N4 heterojunction material for efficient degradation of ciprofloxacin pollutants in water, with sustained high degradation efficiency over multiple cycles. The enhanced photocatalytic activity of the composite material is mainly attributed to accelerated electron and hole separation and transfer through the formation of heterojunctions, which promotes the generation of more SO4 center dot- and center dot OH by stimulating PMS.