A covalent organic framework membrane with electron-enriched channels for modulating hydrated zinc ion transport

Abstract

A covalent organic framework (COF) membrane with ketoneenamine and triphenylamine units was designed to modulate hydrated Zn²⁺ transport in aqueous zinc-ion batteries. Electronenriched COF channels adsorb Zn²⁺ and displace coordinated water, reducing Zn²⁺ hydration while providing defined hopping sites that enhance Zn²⁺ conduction. This dual regulation suppresses dendrite growth and parasitic reactions at the zinc anode, stabilizing Zn plating/stripping. Electrochemical tests in symmetric and full batteries show markedly improved cycling stability and rate performance. The study demonstrates a strategy to regulate the ion solvation environment via porous membranes, highlighting COFs as functional interlayers for controlled electrolyte-ion interactions.