Eu2O3/Co3O4 nanosheets for levofloxacin removal via peroxymonosulfate activation: Performance, mechanism and degradation pathway

In this study, Eu2O3/Co3O4 nanosheets (NSs) were successfully synthesized and employed to degrade levofloxacin (LVX) via peroxymonosulfate (PMS) activation. Owing to the enhanced transfer efficiency of Co2+/Co3+ and more adsorbed oxygen, the obtained Eu2O3/Co3O4 NSs displayed better catalytic performance for PMS activation toward LVX degradation than pure Co3O4. The Eu2O3/Co3O4 NSs can remove 97.93% of LVX only in 6 min via activating PMS, with a reaction rate constant (0.2346 min-1) , which was 2.3 folds of single Co3O4 NSs (0.1003 min- 1). Besides, Eu2O3/Co3O4 exhibited good catalytic performance in presence of different inorganic anions, satisfactory stability and reusability. Singlet oxygen (1O2), hydroxyl radical (center dot OH), sulfate radical (SO4 center dot-; ) and superoxide radical (center dot O2-; ) contributed to LVX degradation and 1O2 played the most key role. In addition, based on the ROSs and LVX degradation intermediates, the possible mechanism and degradation pathways of LVX were further cleared in detail. This work can provide a reference for the eco-friendly and facile preparation strategy of efficient and stable catalysts for rapid and efficient removal of recalcitrant pollutants.

Automated summary

In this study, Eu2O3/Co3O4 nanosheets were successfully synthesized and used to activate PMS for degrading LVX, exhibiting better catalytic performance compared to pure Co3O4. The Eu2O3/Co3O4 nanosheets efficiently removed 97.93% of LVX in just 6 minutes, with singlet oxygen playing a key role in the degradation process. Additionally, Eu2O3/Co3O4 showed good stability and reusability, making them a promising candidate for the rapid and efficient removal of recalcitrant pollutants.