Molecularly Programmed Twisting in Hydrogen‐Bonded Organic Crystal Enables Anhydrous Superprotonic Conductivity at High Temperatures

Abstract

Abstract A Hydrogen‐Bonded Organic Crystal (HOC‐88) is reported that achieves unprecedented anhydrous superprotonic conductivity through a molecular topology‐driven hierarchical assembly strategy. Single‐crystal analysis uncovers a saddle‐distorted π‐conjugated monomer with eight phenolic hydroxyl groups, whose synergistic geometric confinement enables spontaneous formation of self‐templated 3D proton highways‐a phenomenon yet to be observed in crystalline organic conductors. The double torsion of the π‐system induces helical cooperativity between hydrogen‐bonded lamellae and π – π stacked columns, generating interconnected proton pathways with negative thermal expansion behavior along the c ‐axis. This unique mechanism allows HOC‐88 to maintain ultrastable proton conduction without humidity dependence, surpassing all known HOCs and routing state‐of‐the‐art MOF/COF analogues. Crucially, the framework demonstrates chemical omniphobicity‐retaining crystallinity in boiling water (100 °C), concentrated acid (0.5  m H 2 SO 4 and 1  m HCl), and 300 °C in air conditions. When deployed in an H 2 ‐O 2 fuel cell prototype, it establishes the first experimental evidence of HOC operating in practical high‐temperature electrochemical devices. The findings reveal that controlled helical distortion in π‐systems can programmatically dictate long‐range proton ordering, opening an unexplored dimension for designing next‐generation solid electrolytes.