Hierarchical Manganese Dioxide/Poly(3,4-ethylenedioxythiophene) Core-Shell Nanoflakes on Ramie-Derived Carbon Fiber for High-Performance Flexible All-Solid-State Supercapacitor

We have proposed a kind of environment-friendly biological carbon fiber material derived from ramie for supercapacitor application. MnO2 nanoflakes were electrochemically grown on the ramie derived carbon fibers (RCFs) with a PEDOT conductive polymer wrapping layer uniformly coated on the flake surface to enhance the electrochemical performance. Benefited from the ultrahigh electron transmission rate of the RCFs backbone, high capacitive activity of MnO2, impressive electrical conductivity of PEDOT film and synergistic effect among above three components, the hybrid electrode displayed a high specific capacitance with 922 F g(-1) at a current density of 1 A g(-1) and remarkable rate capability with capacitance retention of 345 F g(-1) at even 40 A g(-1). An extremely flexible all-solid-state symmetric supercapacitor device based on the hybrid electrode was fabricated. It exhibited outstanding energy output efficiency (delivered an energy density of 19.17 Wh kg(-1) at a power density of 500 W kg(-1)), high capacity retention rate (the capacity still retained 83% over 10000 cycles) and remarkable flexibility, showing its attractive prospect in wearable electronics and sustainable energy application.