Enhancement of ionizing radiation-induced catalytic degradation of antibiotics using Fe/C nanomaterials derived from Fe-based MOFs

Abstract

In present work, we studied a novel Fe/C nanomaterial fabricated using Fe-based metal organic frameworks (MOFs) as precursors through thermal pyrolysis to catalyze gamma irradiation-induced degradation of antibiotics, cephalosporin C (CEP-C) and sulfamethazine (SMT) in aqueous solution. The MOFs-derived Fe/C nanomaterials (DMOFs) had the regular octahedrons structure of MOFs and contained element C, Fe and O, while Fe° with a fraction of Fe3O4 and Fe2O3 were identified. Results showed that DMOFs addition could accelerate the generation of OH during gamma irradiation, while the intermediates of bonds cleavages of antibiotic molecules and OH addition were identified. DMOFs were more effective to improve the decomposition of antibiotic having the higher adsorption capacity like SMT. The degradation rate of CEP-C and SMT increased by 1.3 times and 1.8 times, and TOC reduction at 1.0 kGy reached 42 % and 51 %, respectively by gamma/DMOFs treatment, while only 20.2 % (CEP-C) and 4.5 % (SMT) of TOC reduction were obtained by γ-irradiation alone. The crystal structure, functional groups and magnetism of DMOFs changed slightly after gamma irradiation, which made it possible to be reused. DMOFs were promising to enhance the degradation of antibiotics during gamma irradiation.