Interconnected polypyrrole nanostructure for high-performance all-solid-state flexible supercapacitor - Carbon4Energy

Rational design of conductive polymer-based supercapacitor (CPSC) by integrating three-dimensional (3D) interconnected electrode materials with porosified electrolyte is of great potential to simultaneously increase the specific capacitance and rate capability of CPSC device. Herein, we describe for the first time a prototype of all-solid-state CPSC using 3D interconnected fibrous polypyrrole (PPy) and 3D porosified electrolyte. The as-made PPy was characterized to possess excellent electron conductivity (~7.8 S·cm-1), 3D interconnected structure, providing fast electron/ion transportation pathway to accelerate the kinetics of interfacial pseudocapacitive reactions. The symmetric PPy-based CPSC device initially delivered a high specific capacity up to 505 mF·cm–2 at current stream of 2.0 mA·cm–2 and was capable of retaining 50% capacitance (~250 mF·cm–2) at high rate (20.0 mA·cm–2). Meanwhile, an improved energy density of 44.9 μWh·cm-2 at power of 8 mW·cm-2 was achieved. In addition, PPy-CPSC exhibited excellent flexible performance, no obvious degradation of capacitive performance was observed for PPy-CPSC device under bent or twisted.