Template free N-doped 3D porous carbon@Co3O4: Towards highly efficient catalysis for peroxymonosulfate degradation of antibiotics

Abstract We report on a new type of nitrogen-doped porous carbon@Co3O4 catalysts, demonstrating high-efficiency for tetracycline (TC) degradation, are synthesized via two steps of simple grinding and calcination treatment. The temperatures of carbonization and oxidation play an important role in determining the structure, morphology, chemical composition and catalytic performance of the catalysts. The C-700-300 catalyst with 3D porous structure demonstrates the best catalytic performance for TC degradation due to the large amount of graphitized nitrogen, large specific surface area and small particle size. The effect of catalyst and peroxymonosulfate (PMS) amount on the catalytic performance are also fully investigated. The mechanism of catalysts to PMS activation for TC degradation is elaborated, which is ascribed to the radical and non-radical pathways. The sulfate radical function in TC degradation from the radical quenching experiment and the non-radical pathway is also discussed to complement the above degradation due to the excessive electron donors in catalysts.