Homogeneous Carbon Dot-Anchored Fe(III) Catalysts with Self-Regulated Proton Transfer for Recyclable Fenton Chemistry

[Image: see text] Fenton chemistry has been widely studied in a broad range from geochemistry, chemical oxidation to tumor chemodynamic therapy. It was well established that Fe(3+)/H(2)O(2) resulted in a sluggish initial rate or even inactivity. Herein, we report the homogeneous carbon dot-anchored Fe(III) catalysts (CD-COOFe(III)) wherein CD-COOFe(III) active center activates H(2)O(2) to produce hydroxyl radicals ((•)OH) reaching 105 times larger than that of the Fe(3+)/H(2)O(2) system. The key is the (•)OH flux produced from the O–O bond reductive cleavage boosting by the high electron-transfer rate constants of CD defects and its self-regulated proton-transfer behavior probed by operando ATR-FTIR spectroscopy in D(2)O and kinetic isotope effects, respectively. Organic molecules interact with CD-COOFe(III) via hydrogen bonds, promoting the electron-transfer rate constants during the redox reaction of CD defects. The antibiotics removal efficiency in the CD-COOFe(III)/H(2)O(2) system is at least 51 times large than the Fe(3+)/H(2)O(2) system under equivalent conditions. Our findings provide a new pathway for traditional Fenton chemistry.