3D-interconnected framework binary composite based on polypyrrole/textile polyacrylonitrile-derived activated carbon fiber felt as supercapacitor electrode

Supercapacitors have been studied due to their promising as powerful storage devices. The development of highly efficient electrodes is one way to manufacture supercapacitors with high energy and power efficiencies. Binary composites based on activated carbon fiber felt (ACFF) and polypyrrole (PPy) have been investigated to increase capacitance performance. ACF, when applied as a bulk electrode has limited electric characteristics while the PPy suffers from limited stability during cycling that reduces the initial performance. Based on the synergism effect, this work proposes the production of a binary composite based on ACFF produced from a low-cost precursor textile polyacrylonitrile (textile PAN) and the facile synthesis of PPy from the chemical route of polymerization. The binary composite formed by a 3D network with the interconnection of a more conductive form of PPy coated on ACFF was obtained. The resulting architecture was determinant to significantly increase the energy storage capacities when compared to the bulk ACFF electrode. From the galvanostatic charge and discharge curves, cyclic voltammetry and electrochemical impedance, the obtained composite had a specific capacitance about 302 F g⁻¹ associated with low resistance and to a good density of energy and power.