Sustainable water decontamination in a fluidic sequential electrochemical reactor

Here, we demonstrate an integrated fluidic sequential electrochemical system for effective water decontamination. The system consists of a Ti mesh anode deposited with nanoscale IrO₂ and a CNT filter functionalized with nanoconfined Fe₂O₃. By conducting anodic oxygen evolution reaction (OER) and 2e^– oxygen reduction reaction (ORR) sequential electrolysis, our system enables sustainable O₂ generation at the anode, followed by transformation of O₂ into H₂O₂ at the cathode, which then led to the production of ¹O₂ in the presence of nanoconfined Fe₂O₃. No chemical inputs were needed nor side products occurred during the whole sequential electrochemical processes. The effectiveness of the system was evaluated using tetracycline as a model emerging contaminant. Recirculating at 3 mL min^–1, the system exhibited negligible iron and iridium leaching (≤0.01 mg L^–1) and high tetracycline degradation efficiency (≥95%). Such excellent efficacy can be maintained across a wide pH range and in complicated water matrices.