Co-TCPP/MXene film electrodes and patterned interdigital electrodes with high performance for flexible all-solid supercapacitors

With the development of electronic technology, portable and wearable electronics are becoming increasingly indispensable in our lives, which promotes a high demand for flexible power supplies. To develop lightweight, flexible, and high performance energy storage devices, we have prepared MXene and Co-TCPP nanosheet composites (CoMX) with excellent electrochemical properties by electrostatic self-assembly. Co-TCPP is inserted between MXene layers and successfully improves ion accessibility and enhances electrochemical performance. CoMX film electrodes fabricated by vacuum filtration show high specific capacitance (1591.7 mF/cm²) and exhibit excellent cycling stability, with a capacity retention rate of 99.81 % after 8000 cycles. Flexible all-solid-state supercapacitors (SC) assembled with CoMX film and interdigital electrodes both exhibit excellent capacitance performance. The in-plane SC exhibits competitive specific capacitance (330.0 mF/cm²) and energy density (37.13 μWh/cm² at 450 μW/cm²). The specific capacitance and energy density of interdigital SC achieve 89.9 mF/cm² and 12.9 μWh/cm², respectively. The competitive performance of both devices makes them highly promising for flexible energy storage devices.