A Composite of Hierarchical Porous MOFs and Halloysite Nanotubes as Single‐Ion‐Conducting Electrolyte Toward High‐Performance Solid‐State Lithium‐Ion Batteries

Abstract Metal–organic frameworks (MOFs), as a promising rechargeable electrochemical energy storage material have emerged in the field of solid‐state lithium batteries. However, low ionic conductivity and high interfacial impedance still severely hamper the application of MOF‐based solid‐state electrolytes (SSE). In this work, a novel hierarchical porous H‐ZIF‐8 solid‐state electrolyte (SSE) material is harvested through the in situ growth of zinc nitrate hydroxide nanosheets, expressing excellent ion conductivity of 1.04 × 10 −3 S cm −1 and Li + ‐transference number of 0.71. Moreover, the morphology and structure of H‐ZIF‐8 is further optimized to obtain a composite H‐ZIF‐8/HNT by decorating halloysite nanotubes (HNT). Notably, functionalized H‐ZIF‐8/HNT as an electrolyte presents obvious enhancement on electrochemical properties: higher ionic conductivity of 7.74 × 10 −3 S cm −1 , better single‐ion transmittability ( = 0.84), good interfacial compatibility as well as excellent rate performance. More importantly, the Li/LiFePO 4 battery equipped with H‐ZIF‐8/HNT SSE has efficient lithium‐dendrite suppression and up to 84% capacity retention (104.16 mA h g −1 ) after 200 times galvanostatic charge/discharge cycles. This work enriches the solid‐state lithium‐ion composite electrolyte materials, opening an entirely new way for enhancing electrochemical performance.