LaCoO₃/SBA-15 as a high surface area catalyst to activate peroxymonosulfate for degrading atrazine in water

An efficient perovskite-based heterogeneous catalyst is highly desired to activate peroxymonosulfate (PMS) for removing organic pollutants in water. A high surface area PMS-activator was fabricated by loading LaCoO₃ on SBA-15 to degrade atrazine (ATR) in water. The LaCoO₃/SBA-15 depicted better textural properties and higher catalytic activity than LaCoO₃. In 6.0 min, atrazine (ATZ) degradation in the selected LaCoO₃/SBA-15/PMS system, LaCoO₃, adsorption by LaCoO₃/SBA-15, sole PMS processes reached approximately 100%, 55.15%, 12.80%, and 16.65 % respectively. Furthermore, 0.04 mg L^-1 Co was leached from LaCoO₃/SBA-15 during PMS activation by LaCoO₃/SBA-15. The LaCoO₃/SBA-15 showed stable catalytic activity after reuse. The use of radical scavengers and electron paramagnetic resonance spectroscopy (EPR) demonstrated that ROS such as ¹O₂, O₂^•-, ^•OH, and SO₄^•- were generated by PMS activated by LaCoO₃/SBA-15 owing to redox reactions [Co²⁺/Co³⁺, and O^2-/O₂]. EPR, XPS, ATR-FTIR, EIS, LSV, and chronoamperometric measurements were used to explain the catalytic mechanism for PMS activation. Excellent atrazine degradation was due to high surface area, porous nature, diffusion-friendly structure, and ROS. Our investigation proposes that perovskites with different A and B metals and modified perovskites can be loaded on high surface area materials to activate PMS into ROS.