ZrO2-supported LaCo0.5Cu0.5O3 composites for enhanced peroxymonosulfate activation and efficient degradation of ibuprofen.

The tight packing of perovskite particles and secondary pollution limit their peroxymonosulfate (PMS) activation efficiency for water treatment. To address this, an eco-friendly and stable LaCo0.5Cu0.5O3/ZrO2 (LCCZ) catalyst is synthesized via a sol-gel method. Cu is introduced into the B-site of LaCoO3 to form LaCo0.5Cu0.5O3 (LaCoCu55) and then supported on ZrO2. Characterization results confirmed the successful synthesis and dispersion of catalyst. Cu doping promoted Co3+/Co2+ and Cu2+/Cu+ redox cycles, while the ZrO2 support enhanced active site exposure. Under optimized conditions (25 °C, 20 mg L-1 ibuprofen (IBU), 0.1 g L-1 LCCZ, 0.75 mM PMS, pH 7), IBU was completely degraded within 30 min. The catalyst exhibited good recyclability with minimal Co leaching (0.522 mg L-1). After modification to form LCCZ, the enhanced redox cycling between Cu and Co ions, coupled with improved accessibility of active sites to PMS facilitated by the ZrO2 support, synergistically activated PMS to generate substantial amounts of reactive species including 1O2 and ˙SO4 -. IBU degrades via 1O2 and ˙SO4 --mediated oxidation, forming benzene-ring intermediates before mineralization to CO2 and H2O. This work guides perovskite catalyst design for IBU wastewater treatment by PMS activation.