A sustainable and metal-free advanced oxidation process for efficient water purification by electrified reduced graphene oxide membrane

The catalyst efficiency-stability trade-off still remains the major challenge for advanced oxidation processes (AOPs). To overcome this challenge, herein, we develop a sustainable and metal-free AOP by an electrified reduced graphene oxide (rGO) membrane in the flow-through electrochemical membrane system, demonstrating efficient degradation of a broader range of water contaminants (>90%), significant reduction of the effluent toxicity (harmless effluent) via the electrochemical activation of peroxymonosulfate (PMS), and long-term stability (>50 h) even in various real water matrices. The external electric field maintains the morphology of rGO and promotes the redox cycle between C–O and C=O groups of rGO at the cathode, with the electrochemical regenerated C–O groups providing sustainable active sites for the formation of rGO-PMS∗, ensuring the long-term stability of the electrified rGO membrane. This work paves the way toward the application of cheap carbonaceous catalysts for effective and sustainable water purification and decontamination.