Co isomorphic substitution for Cu-based metal organic framework based on electronic structure modulation boosts Fenton-like process

Abstract

Regulation of active sites is of significant importance for boosting the catalytic properties of metal–organic frameworks (MOF). Herein, we developed a one-pot strategy to construct bimetallic organic frameworks with Cu-Co double sites (CuCo-MOF) for peroxymonosulfate (PMS) activation. CuCo-MOF exhibits excellent active oxidation capacity, enabling complete removal of NIM within 25 min (0.227 min−1). Its NIM degradation rate was 7.3 and 2.4 times higher than that of Cu-MOF and Co-MOF, respectively. The theoretical simulations unravel that doping Co into the lattice structure of Cu-MOF promotes electron transfer from the electron-rich region (benzene ring) to the electron-deficient regions around metal sites, which facilitated the optimization of the adsorption energy for PMS activation and boosted the breakage of OO bond in PMS. According to LC-MS analysis and DFT calculation, the NIM degradation pathways were proposed, and its degradation intermediates were conducted for toxicity evaluation. The findings, revealing the synergistic effect of bimetals, open a new avenue for the rational design of highly efficient MOF-based Fenton-like catalysts.