Synergistic Integration of Redox-Active Deep Eutectic Gel Electrolyte and Hierarchical CNT@ZIF-Derived Porous Carbon...

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 LiClO₄, dimethyl sulfoxide, water, and K₃[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.