High-entropy perovskite embedded in carbon-based catalyst toward peroxymonosulfate activation to degrade Rhodamine B: Performance and mechanism insights

Advanced oxidation processes (AOPs) based on peroxymonosulfate (PMS) enable efficient generation of highly oxidative radicals for eliminating diverse organic pollutants. Developing multi-active, stable catalysts remains challenging. In this study, a composite catalyst integrating high-entropy perovskite oxides (HEPs) with carbon microspheres (CS), denoted as HEPs@CS, was successfully synthesized to activate PMS for generating reactive oxygen species (ROS), enabling efficient degradation of Rhodamine B (RhB, 99.7 % removal in 10 min), tetracycline (TC), and other pollutants via a singlet oxygen ( 1 O 2 )-dominated nonradical pathway, with a high rate constant (0.5815 min -1 ). The HEPs framework, featuring a multi-active-site co-catalytic system and strong metal-support interactions (MSI), exhibited exceptional catalytic activity and stability. Through EPR, FT-IR, and Raman characterization tests, the material's exceptional performance is also attributed to the synergistic participation of oxygen vacancies (O V ), diverse carbon surface functional groups, and defect structures in the reaction system. These factors collectively enhance electron transfer during both PMS activation and pollutant degradation processes. ECOSAR software confirmed the environmental safety of this process. Our findings demonstrate that HEPs@CS exhibits outstanding performance as a PMS activator for wastewater treatment of organic pollutants. This work provides deeper insights into how polymetallic electronic structures in high-entropy perovskites modulate PMS activation mechanisms.