Innovative Bipolar Co-Planar Janus Membranes for High-Efficiency Electrocatalytic Filtration and Sustainable Water Reuse

Addressing global water scarcity necessitates the adoption of flexible, decentralized, and energy-efficient membrane technologies. In this study, a bipolar coplanar Janus membrane (BPCPM) is proposed that integrates anodic and cathodic electrodes on a common membrane surface, addressing module-compatibility challenges in conventional electrofiltration for water recycling. Peano curves, based on fractal geometry, are utilized to create unique patterns for positioning the anode and cathode, maximizing the electric field intensity and reactive species on the membrane surface. Applying a platinum-coated BPCPM prototype with an optimized fractal configuration, we have achieved a highly efficient cogeneration of HClO and H 2 O 2 in dual-pulse flow-through electrofiltration operation with minimal energy consumption (0.17 kWh per m 3 permeate). The BPCPM delivers 100% surface retention of Escherichia coli and Staphylococcus aureus, facilitating a greater than 5-log reduction in bacterial viability and representing effective antibacterial activity. A scaled-up BPCPM reactor was evaluated for practical aquaculture wastewater reuse in crop irrigation. Over a 14 day period of operation, the modularized reactor exhibited a robust water flux and long-term biofouling resistance, demonstrating excellent BPCPM durability and scalability. The efficient removal of hazardous antibiotics and pathogens generated a nontoxic permeate, while also effectively supporting plant growth by enhancing nitrogen availability. The proposed innovative, scalable, and energy-efficient BPCPM electrofiltration platform offers a practical route to decentralized, sustainable water reuse.