Biomimetic Ionic COF Channels Enable Grotthuss Hydroxide Conduction in PAA Gels for Dendrite‐Free Quasi‐Solid Zinc‐Air Batteries

ABSTRACT Quasi‐solid‐state zinc‐air batteries (ZABs) are promising for safe and scalable energy storage, yet gel electrolytes often suffer from sluggish hydroxide transport, severe polarization, and zinc dendrite growth. Here we develop an ionically modified covalent organic framework/polyacrylic acid gel electrolyte (COF@PAA) that converts COFs from passive porous fillers into active OH − ‐conduction scaffolds. High‐throughput screening identifies COF building blocks with optimal compatibility toward PAA, enabling robust integration and a strengthened gel network. Ionic functionalization introduces fixed charged sites within ordered COF channels, constructing a continuous hydrogen‐bond network and hopping nodes that facilitate Grotthuss‐type OH − structural diffusion beyond conventional vehicle transport and reduce OH − trapping. Molecular dynamics simulations confirm that the OH − diffusion coefficient is approximately 3.6 times higher than that of pure PAA. The COF@PAA gel delivers high ionic conductivity (290 mS cm −1 ), a wide electrochemical window (1.9 V), improved water retention (78.31% after 120 h), and excellent stretchability (485% strain). In Zn‐air cells, the rapid replenishment of OH − at the electrode interface homogenizes ion flux, effectively suppresses dendrite growth, and enables stable cycling for 145 h. Meanwhile, the overall efficiency and reliability of flexible ZABs are improved.