Boosting Mass Transfer and Electron Kinetics in PMS Activation: D-Band Modulation via Nitrogen-Coordinated Cobalt Catalysts

Mass transfer limitations in Co-based heterogeneous peroxymonosulfate (PMS) activation systems were effectively mitigated via electronic structure modulation. Nitrogen doping introduces electron-withdrawing effects into Co/NC catalysts, which shifts the Co d-band center upward and optimizes orbital hybridization between the Co 3d and O 2p orbitals. This electronic configuration lowers the antibonding state occupancy in the Co-PMS complex, thereby facilitating PMS adsorption and activation. The engineered Co/NC catalyst completely degrades sulfamethoxazole within 3 min (rate constant: 2.3 min–1), demonstrating enhanced interfacial electron transfer kinetics. Its robust performance is maintained in complex aqueous matrices containing Cl–, NO3–, H2PO4–, and SO42– anions. Moreover, effective pollutant removal persists for over 240 min in a continuous-flow membrane reactor, confirming the practical applicability. This orbital-level design strategy advances cobalt-based PMS activation systems by synergistically optimizing the mass transfer and electronic interactions.