Enhanced and synergistic catalytic peroxymonosulfate activation degradation of OFX by photoexcitation driven Bi2O3@NiFe2O4 Z - scheme heterojunction

The two-step hydrothermal method was used to synthesize Z-scheme heterojunction Bi2O3@NiFe2O4 for photocatalytic activation of peroxymonosulfate (PMS) to degrade ofloxacin in simulated wastewater. The specific surface area of BNF-2 reached 80.69 m2/g, with a mesopore size of approximately 10 nm. At a Bi/Ni/Fe molar ratio of 2:1:2, the kinetic rate of Ofloxacin (OFX) degradation in the BNF-2/Vis/PMS system was 3.49 and 2.18 times higher than that achieved by PMS or photocatalysis alone. The BNF-2/vis/PMS system effectively eliminated OFX throughout a broad pH range and in wastewater containing various anions. After 5 cycles, the composite maintained excellent cyclic stability and magnetic recovery property. center dot O2-was identified as the major reactive species in the degradation of OFX by electron paramagnetic resonance studies and quenching experiments. The synergistic mechanism of Vis and PMS in the catalytic system and the possible degradation pathway of ofloxacin were proposed. By forming a strong binding and stable structure, the agglomeration of nanoparticles was mitigated, facilitating the recovery and reuse of the composite catalyst and providing more options for the removal of antibiotics in pharmaceutical wastewater.