Photocatalytic in situ H2O2 production and activation for enhanced ciprofloxacin degradation over CeO2-Co3O4/g-C3N4:key role of CeO2

The abused ciprofloxacin antibiotics have caused significant environmental damage.Although oxidative degradation of ciprofloxacin exhibits promising efficacy,it often entails excessive energy consumption.Hence,it is necessary to explore an effective and ecologically sustainable degradation strategy.Herein,we demonstrated that g-C3N4decorated with the coordinated CeO2and Co3O4(CeO2-Co3O4/CN) exhibited effective ciprofloxacin photodegradation via in situ H2O2production and activation mechanism.Results indicate that the introduced CeO2enhances the transference of photogenerated electrons to O2by adjusting the oxygen vacancy of photocatalyst,thereby increasing the generation of superoxide radicals,which in turn generate H2O2,resulting in a 22.4-fold increase in H2O2generation over g-C3N4.Moreover,the in situ H2O2generation facilitated by CeO2is confirmed to be essential for ciprofloxacin degradation via CeO2-Co3O4/CN,as it provides enough oxidant for Co3O4to activate into hydroxyl radicals for the pollutants degradation.Ultimately,CeO2-Co3O4/CN achieves a ciprofloxacin degradation ratio of 97.7% within 80 min.This study introduces a novel approach that combines H2O2generation and activation,offering an innovative perspective for achieving clean and efficient purification of antibiotic-contaminated water.