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

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.