Fabrication of symmetric supercapacitor based on relatively long lifetime polyaniline grown on reduced graphene oxide via Fe2+ oxidation sites

Reduced graphene oxide and polyaniline (RGO-PANI) composite was prepared via functionalized ferrite on graphene oxide as corresponding PANI nucleation sites, which dramatically increase the composite specific capacitance and lifetime when compared with crude PANI. Symmetric paper-based supercapacitors (SCs) were fabricated and electrochemically tested using different electrolytes namely; KOH, H2SO4, H3PO4 and Na2SO4. Therefore, strong alkaline, strong acid, weak acid and natural electrolytes impact on the composite was studied. The influence of various electrolytes was studied intensively using Bio-Logic VSP-300 where cyclic voltammetry, Galvanostatic charge/discharge and impedance spectroscopy tests were applied. The highest achieved specific capacitance was more than 500 F/g of pure electric double layer behavior coupled with 100% retention after 5000 cycles. The composite was characterized using X-ray diffraction, scanning electron microscopy, Raman spectroscopy, and transmission electron microscopy.