Revealing the synergistic mechanism of generation, release, migration and utilization of reactive oxygen species through tailoring the d-band in metal organic frameworks for water purification

Reactive oxygen species (ROS) play important roles in environmental, chemical and biological fields, but the controlled release and migration of ROS remain a major challenge. Here, a highly efficient catalyst (Cu-MIL-101(Fe)) by modifying the electronic structure was designed. The orbital hybridization achieves a deep optimization of the d-band (d band center shifted from −1.01 eV to −1.32 eV), which reduces bonding and antibonding orbitals energy levels, thus promoting release of SO4·-. More importantly, the interfacial micro-electric field (IMEF) formed by the intramolecular charge offset mediates the directional migration of SO4·- from Fe sites to Cu sites. These properties endow the catalyst with high-efficiency SO4·- generation, rapid release, directional migration and utilization, with a 4.3-fold increase in effective oxidant utilization over Fe2+ (from 17.12% to 73.54%). This study highlights a catalytic strategy for efficient ROS generation, release, migration and utilization for a wide range of potential applications including environmental remediation.