High-performance, flexible, all-solid-state, asymmetric supercapacitors from recycled resin-based activated carbon, MnO₂, and waste nonwoven materials

Polymer waste is a global problem. How to convert it into high value-added applications has been a challenge. Herein, we prepare a flexible all-solid-state asymmetric supercapacitor using carbon fiber composite waste resin and disposable nonwoven fabrics as starting materials. For this purpose, we prepared activated carbon (RAC) from the waste resin, and then loaded MnO2 on the RAC. In parallel, we applied a silver paste to the waste nonwoven fabric. By loading RAC and MnO2-RAC separately onto the silver-coated nonwoven, they were used as the negative and positive electrodes to form an all-solid-state supercapacitor with 6.0 M KOH/PVA solid electrolyte. The devices have a specific capacitance of 148.7 F/g with an energy density of similar to 52.9 Wh/kg. After 10,000 charge/discharge cycles, the devices have a capacitance retention rate of 83.9 %, indicating excellent cycle life. They also have excellent flexibility, maintaining the high capacitance almost unchanged under various bending conditions.