Synergistic Integration of Redox‐Active Deep Eutectic Gel Electrolyte and Hierarchical CNT@ZIF‐Derived Porous Carbon for Advanced Micro‐Supercapacitors

ABSTRACT The progression of miniaturized energy storage solutions necessitates the harmonious integration of high energy density, mechanical flexibility, and environmental resilience. In this study, we introduce a high‐performance quasi‐solid‐state micro‐supercapacitor (MSC) that utilizes a synergistic design approach: a redox‐active hybrid deep eutectic solvent (HDES) gel electrolyte in conjunction with a hierarchically structured carbon nanotube coated with ZIF‐8‐derived porous carbon electrode (designated as CNT@ZFC). The optimized electrolyte formulated from LiClO 4 , dimethyl sulfoxide, water, and K 3 [Fe(CN) 6 ] delivers a high ionic conductivity (1.4 mS cm −1 ) and a broad electrochemical stability window (2.5 V), facilitating rapid ion transport and stable redox reactions. Complementing this, the CNT@ZFC electrode provides a robust electron‐conductive framework with a high surface area, ensuring maximum accessibility to electroactive sites. The resulting MSC achieves a superior areal capacitance of 26.04 mF cm −2 at 0.2 mA cm −2 , a maximum energy density of 0.015 mWh cm −2 , and an exceptional stability of 97.3% retention. Notably, the device demonstrates remarkable environmental adaptability, maintaining stable electrochemical performance down to −20°C. This work provides a scalable strategy for integrating redox‐enhanced DES electrolytes with conductive hybrid carbon architectures to advance the next generation of robust, high‐energy miniaturized power sources.