High metal-loaded sub-nanocluster catalyst enhanced Fenton-like reaction activity for emerging contaminants degradation by generating high-valent copper

High-valent copper (Cu(III)) species are crucial intermediates in CH bond functionalization within both the biological and biomimetic processes, facilitated by copper enzymes and stabilized by multicopper oxidases. Herein, a nitrogen-doped copper sub-nanocluster catalyst (SNC) featured a high metal content (29.1 wt%) and uniform Cu distribution was synthesized by carbonizing the nanosheet-like metal–organic framework (MOF), enhancing bisphenol A degradation by activating peroxymonosulfate (PMS) to generate Cu(III). The degradation performance of the SNC outperformed the catalyst carbonized with the bulk-like MOF and matched the reported single-atom catalysts counterparts. Nitrogen doping decreased the electrons of Cu3d orbital, enhancing its bonding with the oxygen atom within the PMS molecule, thus promoting Cu(III) generation. The Cu-SNC/PMS system also showed robust resistance against anions, pH changes, and diverse water matrices. Importantly, it can selectively degrade electron-rich pollutants through oxygen atom transfer by Cu(III). This study provided new perspectives into SNC preparation, the controlled formation of high-valent metal species, and their role in Fenton-like reactions for pollutants degradation.