Flexible supercapacitors are of great significance for the development of intelligent electronic products and wearable devices. Herein, through reasonable design, self-supporting flexible film composites that can be used as supercapacitor electrodes, are synthesised by vacuum filtration. The composites are composed of electrochemically exfoliated graphene nanosheets and MnO₂ nanowires, in which the graphene nanosheets mainly play the role of skeleton support, enhance conductivity, and provide electric double-layer capacitance, while the MnO₂ nanowires mainly provide pseudocapacitance. Results show that the sample with 20 % MnO₂ possesses the best electrochemical performance due to the mass ratio which can give full play to the pseudocapacitive properties of MnO₂ and the conductivity of graphene. The maximum mass specific capacitance reaches 106.2 F g⁻¹ at 0.5 A g⁻¹, and the areal specific capacitance is 767.0 mF cm⁻² at 1 mA cm⁻². The electrode also maintains 86.7 % of the initial capacitance after 10000 cycles, indicating good cyclic stability. Furthermore, an asymmetric solid supercapacitor based on flexible thin films is assembled. The energy density is 20.7 W h kg⁻¹, the power density is 1000 W kg⁻¹, and the capacitance remains 84.2 % after 3000 cycles at 5.0 A g⁻¹. These results suggest that the as-prepared self-supporting material has the potential to be used to construct flexible supercapacitors for wearable equipment.

柔性超级电容器对于智能电子产品和可穿戴设备的开发具有重要意义。在此，通过合理的设计，通过真空过滤合成了可以用作超级电容器电极的自支撑柔性膜复合材料。该复合材料由电化学剥离的石墨烯纳米片和MnO ₂纳米线组成，其中石墨烯纳米片主要起到骨架支撑，增强导电性和提供双电层电容的作用，而MnO ₂纳米线主要提供假电容。结果表明，样品中含有20％MnO ₂由于质量比，MnO ₂具有最佳的电化学性能，可以充分发挥MnO ₂的准电容性能和石墨烯的电导率。最大质量比电容达到106.2 F G ^-1 0.5 A G ^-1，且面积比电容是767.0 mF及其厘米^-2在1mA厘米^-2。10000次循环后，电极还保持初始电容的86.7％，表明良好的循环稳定性。此外，组装了基于柔性薄膜的不对称固体超级电容器。能量密度为20.7 W h kg ^-1，功率密度为1000 W kg ^-1，在5.0 A g下经过3000次循环后电容保持84.2％^-1。这些结果表明，所制备的自支撑材料具有用于构建可穿戴设备的柔性超级电容器的潜力。