Spatial Decoupling Strategy Enhanced Ionic Liquid‐Confined Porous MXene for Breakthrough Osmotic Energy Conversion

Abstract

Abstract The potential of reverse electrodialysis for harvesting osmotic energy is severely limited by ion concentration polarization (ICP), a phenomenon that restricts power output and confines the technology to the laboratory scale (< 0.4 µW). This challenge is overcome with an ionic liquid confined porous MXene (IPM) system that integrates strategies across two scales. At the microscopic level, sub‐nanometer channels are engineered using porous MXene and confined ionic liquids to reduce mass transfer resistance and optimize ion transport. Concurrently, at the macroscopic level, a micropore array design spatially decouples the diffusion interfaces to effectively suppress the ICP effect. This dual‐scale approach increases power density by 53.6% and achieves a maximum output power of 3.47 µW, which is nearly ten times higher than that of similar work. The work demonstrates a robust pathway for overcoming critical power limitations, advancing osmotic energy conversion toward industrial renewable energy applications.