An energetic MOF-assistant confined expansion strategy to fabricate Fe-doped porous carbon beads for advanced oxidation processes: Interfacial reaction mechanism and biological toxicity

Porous carbon material catalysts derived from MOFs-based precursors are gradually being used extensively in advanced oxidation possesses. However, some of the existing problems such as hard to recovery and easy to secondary pollution still need to be solved. Here, a series of Fe-doped energetic metal–organic framework (EMOF)-derived porous carbon spheres (EMFexS) were obtained by the phase inversion route. EMOFs puffed up during pyrolysis at high temperatures to create large-sized hierarchically porous structure. The large specific surface area (483.4 m 2 /g) and high nitrogen content, and hierarchically porous structure endow EMFe 0.2 S with excellent catalytic performance to remove tetracycline removal efficiency. By activating peroxymonosulfate (PMS), it was found that the rate constant (k) in EMFe 0.2 S/PMS system was 0.058 min −1, which was 1.75, 1.56 and 1.52 times than that of EMFe 0 S/PMS system, EMFe 0.1 S/PMS system and EMFe 0.25 S/PMS system, respectively. Experiments and material characterization point that the existence of nitrogen and iron in the catalyst were the potential active sites. The continuous flow catalytic reaction and biological toxicity experiments were employed to evaluate practical application value. This study provides new insights into the preparation of microspheres for water treatment with the help of EMOF-assisted confined expansion strategy.