Facile preparation of SO42−-CoCuFe-LDH as peroxymonosulfate catalyst for efficient degradation of sulfamethoxazole: Performance, reaction mechanism and degradation pathway

In this study, CoCuFe-LDH with SO 4 2− as interlayer anion was prepared by a pot solvothermal method, which exhibited excellent peroxymonosulfate (PMS) activation performance for the degradation of sulfamethoxazole (SMX) over a wide pH range (3.0–12.0). Under the optimal condition, the SO 4 2− -CoCuFe-LDH/PMS system resulted in 99.1 % SMX (10 ppm) degradation in 4 min. Even for 50 ppm SMX, the degradation efficiency and COD removal rate approached 93.3 % and 70.0 % within 10 min, respectively. The current catalyst showed excellent stability after 5 times recycling experiments. The high-valent metal-oxo species were the major reactive oxygen species, and the SO 4 •− , • OH, O 2 •− , and 1 O 2 were involved in the degradation of pollutant. The SO 4 2− interlayer could expand the interlayer spacing of LDH, which facilitated the diffusion of PMS and pollutants within the interlayer and improved the utilization efficiency of the active sites. The current study provided novel insights into the designation of LDH structures in advanced oxidation processes.