In Situ Oxygen Shuttling within a Bilayer Electrified Membrane Enables Aeration-Free Electro-Fenton Water Purification.

Abstract

Electro-Fenton (EF) has emerged as a premier advanced oxidation process in water decontamination, but current EF systems are limited by high-energy-consuming aeration and low oxygen transport efficiency at the electrode-electrolyte interface. Here, we report a flow-through bilayer electrified membrane reactor (BEMR) that integrates in situ oxygen generation and spatial delivery to enable aeration-free EF reaction. In the BEMR, oxygen is continuously generated in situ through the oxygen evolution reaction at the upstream anode and subsequently transported downstream by pressure-driven water flow, establishing a self-sustaining dynamic oxygen shuttling system. Concurrently, an oxygen-philic interfacial microenvironment is constructed at the cathode using a reticular framework with high porosity and strong oxygen affinity, which promotes local oxygen enrichment and reduces boundary layer resistance. This synergistic oxygen regulation transforms the traditional passive diffusion-limited process into an active guided shuttle mechanism, significantly improving interfacial oxygen utilization efficiency and accelerating the generation of reactive oxygen species. The aeration-free EF system achieves rapid and efficient degradation of recalcitrant pollutants, with effects comparable to aeration systems, while reducing total energy consumption by more than 70%. This work advances our understanding of interfacial oxygen regulation in electrochemical systems and promotes the development of energy-efficient EF technologies for sustainable water purification.