Fe and Zn co-doped carbon nanoparticles as peroxymonosulfate activator for efficient 2,4-dichorophenol degradation

Iron-mediated activation of peroxymonosulfate (PMS) has been of great interest for the effective removal of contaminants, but it still suffered from ineffective metal redox cycle rate, which resulted in unsatisfactory catalytic efficiency. Constructing bimetallic carbonaceous materials was effective way to improve the catalytic performance of iron-based heterogeneous system. In this study, magnetic bimetallic porous carbon composite (FZC_x) was synthesized via Fe/Zn bi-MOFs pyrolysis for 2,4-dichlorophenol (2,4-DCP) degradation by peroxymonosulfate. Influences of different systems exhibited that 100% of 2,4-DCP was rapidly degraded at the conditions of catalyst dosage = 0.1 g L^-1, PMS = 0.5 mM and initial pH = 9.0 within 30 min. The as-prepared FZC₆₀₀ displayed excellent reusability and stability. Quenching experiments and EPR analysis manifested that SO₄^·- and ¹O₂ were primarily responsible for the rapid degradation of 2,4-DCP. Moreover, XPS, EPR and EIS was used to elaborate the bimetallic synergy effect, proving that the introduction of zinc can effectively promote periodic cycle of Fe²⁺/Fe³⁺ and improve catalysts durability and reusability. These findings highlighted the preparation of bimetallic based carbonaceous material with excellent PMS activation ability to remove refractory organics from wastewater and provided a depth insight into the promotion of bimetal synergy between zinc and iron on PMS activation process.