Facile one-pot fabrication of ZnO2 particles for the efficient Fenton-like degradation of tetracycline

This work presented a facile one-pot fabrication of zinc peroxide (ZnO2) particles for Fenton-like degradation of tetracycline (TC). The effects of precipitants and their addition sequences on the synthesis of ZnO2 were first investigated in detail. Phase-pure ZnO2 could be obtained when H2O2 was added before adding precipitant (NH3·H2O/NaOH) or after NH3·H2O precipitation. The Fenton-like degradation performance of ZnO2 was evaluated using 100 mL of TC solution (50 mg/L). It was found that 10 mg of ZnO2 could degrade about 90% of TC within 1 h in the presence of 3 mg of Fe2(SO4)3·xH2O at ambient temperature. Besides, increasing ZnO2 dosage, Fe2(SO4)3·xH2O dosage and temperature were all beneficial to TC degradation, and the degradation process could be well described by the pseudo-second order kinetic model. The catalytic degradation process could be efficiently conducted in a wide pH range of 4–8, while the coexisted PO43− and HCO3− were unfavorable for TC degradation. Furthermore, radical quenching experiments and electron spin resonance tests indicated that hydroxyl radical was the dominant reactive oxygen species generated in the degradation system.