Multi‐Dimensional Ion Transport in Biohybrid Hydrogel Electrolytes: Porous Aromatic Framework‐Mediated Dendrite Suppression for Ultrastable Zinc Metal Anodes

Abstract The hydrogel electrolytes (HEs) offer interfacial adaptability for Zn 2+ batteries (ZIBs), however, their practical implementation is hindered by Zn dendrite propagation and inefficient Zn 2+ regulation. In this work, these challenges are addressed by strategically integrating porous aromatic framework (PAF‐222‐SO 3 H) framed with sulfonic acid and amine group into carboxymethyl chitosan‐tannic acid matrix to obtain HE (CTPHE). The hierarchical pore architecture of PAF‐222‐SO 3 H established 3D Zn 2+ transfer highways to make CTPHE exhibit high ionic conductivity of 2.68 S m −1 and Zn 2+ transfer number of 0.72. Meanwhile, the bifunctional groups of PAF‐222‐SO 3 H synergistically manipulated Zn 2+ deposit behavior, in the light that the sulfonic acid moieties generated electrostatic repulsion to homogenize Zn 2+ flux distribution, and the amine sites coordinated with H 2 O to weaken Zn 2 ⁺ solvation shells. Furthermore, the nano‐confinement effect of mesopores promoted the desolvation kinetics effectively. This multi‐dimensional ion transport enabled Zn||Zn cells to sustain 4,000 h cycling (1 mA cm −2 ) with ultralow polarization, and Zn||V 2 O 5 full cells retained 95.1% capacity after 1000 cycles at 1 A g −1 . The success of PAF‐222‐SO 3 H‐based HE design provides a universal paradigm to reconcile ion conduction efficiency with interfacial stability in ZIBs.