Electrochemical polymerization of chloride doped PEDOT hierarchical porous nanostructure on graphite as a potential electrode for high performance supercapacitor

Direct deposition of hierarchal and porous nanomaterials on the substrate has a considerable interest in the development of supercapacitor electrodes due to its simple and low-cost process, the porous surface area improves the charge storage capability and the hierarchical structure capable for more electrolyte infiltration with better ion diffusion. Herein, for the first time, we demonstrated the feasibility of electrochemical polymerization of chloride ions doped (Cl) poly (3, 4-ethylenedioxythiophene) (Cl-PEDOT) porous nanostructures on graphite for supercapacitor electrodes using ferric chloride (FeCl3) as a supporting electrolyte. The optimized deposition and cleansing process offer a well-defined porous hierarchal Cl-PEDOT nanofoam on graphite electrode with the excellent electrochemical properties. The PEDOT porous nanostructure on graphite electrode showed a maximum specific capacitance of 480 F g−1 at 2 A g−1 current density with an outstanding stability of ∼95% after 10,000 charge/discharge cycles in 1 M H2SO4. In addition, the electrodes were assembled into a symmetrical supercapacitor and displayed a maximum specific capacitance of 189 F g−1 with attractive capacitance retention of ∼86% for 10,000 cycles. Furthermore, the device displayed high specific energy of 6.19 W h kg−1 and specific power of 50.12 kW kg−1with excellent rate capability for the higher current densities.