Ultrafast Modification of Copper Chlorophyllin by Magnetic Induction Heating for Water Electrodisinfection by Selective Reduction of Oxygen to Hydrogen Peroxide

The two-electron oxygen reduction reaction has emerged as an effective strategy to replace the anthraquinone process for the on-site green production of hydrogen peroxide that can be used for electrochemical disinfection of water. Herein, sodium copper chlorophyllin is modified by magnetic induction heating at controlled currents (300 to 500 A) for seconds to produce CuNC nanocomposites, where the CuN4 coordination moieties are retained and embedded within a carbon scaffold, as manifested in transmission electron microscopy, X-ray absorption spectroscopy, X-ray photoelectron spectroscopy, and Raman measurements. In electrochemical tests, the CuNC nanocomposites exhibit an apparent electrocatalytic activity toward the selective two-electron oxygen reduction to hydrogen peroxide in alkaline media, and the sample prepared at 400 A for 10 s stands out as the best among the series, with a H2O2 yield close to 90%. Such a unique property can be exploited for on-site water treatment/disinfection, as manifested in the effective degradation of organic dye pollutants (e.g., methylene blue) and removal of waterborne pathogens (e.g., Escherichia coli). Results from this study highlight the unique potential of magnetic induction heating in the ultrafast production of functional nanocomposites as high-performance electrocatalysts for diverse applications.