Sustainable synthesis of modulated Fe-MOFs with enhanced catalyst performance for persulfate to degrade organic pollutants

In this study, four typical modulators (NH4OH(A), CH3COOH(B), CH3COONa(C) and CH3COONH4(D)) were applied to modulate the microwave-assisted synthesis of Fe-MOFs. The effects of various modulators on the yield, electrochemistry activity and PS activation capacity of prepared catalysts were systematically investigated. The ideal modulator was revealed as the 7.5 mM CH3COONH4. Contributed by the defects caused by the dual effects of CH3COONH4, Fe-MOFs-D-7.5/PS system showed excellent orange G (OG) degradation with high reaction stoichiometric efficiency (RSE) and desirable recycling performance. The main radicals should be SO4·- and O2·- which were confirmed by EPR and chemical quenchers. Furthermore, the frontier molecular orbital (FMO) theory and dual descriptor (DD) method were employed in predicting radical attacking sites of OG. According to the results of theoretical computations and experimental detection, degradation pathways of OG in Fe-MOFs-D-7.5/PS system were proposed. Similar to the function of the battery, this study gives new insight into the possible mediatory roles of Fe-MOFs-D-7.5 in PS activation by transferring the electrons between PS and the unsaturated metal sites (CUS). The Fe-MOFs-D-7.5/PS system is a promising process for environmental remediation.