Organic wastewater treatment by a single-atom catalyst and electrolytically produced H 2 O 2

The presence of organic contaminants in wastewater poses considerable risks to the health of both humans and ecosystems. Although advanced oxidation processes that rely on highly reactive radicals to destroy organic contaminants are appealing treatment options, substantial energy and chemical inputs limit their practical applications. Here we demonstrate that Cu single atoms incorporated in graphitic carbon nitride can catalytically activate H2O2 to generate hydroxyl radicals at pH 7.0 without energy input, and show robust stability within a filtration device. We further design an electrolysis reactor for the on-site generation of H2O2 from air, water and renewable energy. Coupling the single-atom catalytic filter and the H2O2 electrolytic generator in tandem delivers a wastewater treatment system. These findings provide a promising path toward reducing the energy and chemical demands of advanced oxidation processes, as well as enabling their implementation in remote areas and isolated communities. Here the authors design an electrolysis reactor to generate H2O2 which could be further catalytically activated by Cu single atoms to yield hydroxyl radicals. Combining the two reactions enables a system that could treat organic wastewater, providing a path toward sustainable advanced oxidation processes.