Chemical Interaction Customized Metal–Organic Framework Enables Regulated Conductive Network for Selective Superionic Conduction in Solid-State Batteries

Solid-state batteries demand solid-state electrolytes (SSEs) that couple high ionic conductivity with high Li⁺ selectivity and broad electrochemical stability, yet these metrics rarely coexist in processable, air-tolerant SSEs. Here, we engineer chemical-interaction-customized metal-organic frameworks (CIC-MOF-X, X = 0, NH₂, OH) via nanoconfined polymerization of a polar guest matrix inside functionalized MOF nanochannels, generating a regulated polar network with programmable host-guest interactions. Hydroxy-decorated CIC-MOF-OH establishes an aggregate-dominated coordination structure that weakens binding toward Li⁺ through coadsorption at framework -OH and carbonyl sites on polymeric chains, while immobilizing TFSI^- by dense hydrogen bonding, enabling hopping-dominated Li⁺ transport. CIC-MOF-OH delivers a high ionic conductivity of 6.1 × 10^-4 S cm^-1, a high Li⁺ transference number of 0.7 at 30 °C, retains conductivity of 5.8 × 10^-4 S cm^-1 after 30 days in humid air, and supports stable Li plating/stripping for 1600 h at 0.2 mA cm^-2. Corresponding LiFePO₄|Li full cells exhibit a capacity retention of 96.5% after more than 4 months of cycling, and NCM811|Li full cells deliver a capacity retention of 83% after 150 cycles at 0.5 C, demonstrating coordination-structure engineering in porous crystals as a general route to selective superionic conduction.