Accelerating Phosphate Transport Across Membranes via Synergistic Chemical‐Electrochemical Carriers

Abstract

Abstract

ABSTRACT Efficient phosphate recovery from phosphate‐containing wastewater presents a dual opportunity to mitigate environmental pollution and secure nutrient supply for agriculture. Among many recovery methods, electro‐membrane crystallization (e‐MC) is a promising strategy for sustainable phosphate recovery, yet the low phosphate throughput of conventional electro‐driven membranes constrains its efficacy. Here, we propose an ion carrier‐to‐carrier hopping transport principle and introduce a nanostructured electro‐driven carrier‐conducting membrane (e‐CCM) engineered with monodispersed electro‐ferrihydrite nanoparticles as a built‐in phosphate carrier. This membrane architecture establishes a coordination environment where ≡FeOH acts as transient phosphate binding sites, and the applied electric field promotes directional phosphate migration, thereby accelerating phosphate permeation. Operated at 5 mA cm −2 , the resulting e‐CCM membrane achieves a phosphate permeation rate of 0.92 mol m −2 h −1 and a recovery rate of 98.8%, outperforming state‐of‐the‐art ion exchange membranes. We further demonstrate scalability by integrating the e‐CCM membrane in e‐MC for processing simulated urine, achieving 93.6% phosphate recovery and the precipitation of high‐purity struvite. This work pioneers a hypothesis of carrier‐conducting construction that synergizes membrane electrochemical transport with chemical affinity, establishing a scalable and energy‐efficient pathway to close the phosphorus loop and advance circular resource economies.