Co-N-C@SiO2 core@shell architectures enhanced stability to activate peroxymonosulfate (PMS) for efficient sulfamethoxazole degradation

Abstract Co-N-C@SiO2 with Co, N doped carbon as core and SiO2 as shell was successfully synthesized by template method, and SiO2 shell was about 43 wt%. Impressively, the SiO2 shell increased the active sites of the core in Co-N-C@SiO2 preparation, and reduced the loss of active sites during use. Co-N-C@SiO2/PMS was a 1O2 dominated non-radical reaction, which was less interfered by solution pH and water constituents. In addition, Co-N-C@SiO2 possessed better cycling performance compared with Co-N-C. Finally, the possible SMX degradation pathways were presented based on the identified intermediate products.