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

Abstract

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.