Structural and Electrochemical Analysis of Activated Carbon Derived from Seeds of Ziziphus jujuba and Shells of Prunus dulcis Decorated over Graphene Oxide/Polyaniline Binary Composite for High Energy Density Supercapacitor Applications

Supercapacitor electrodes synthesized from activated carbon (AC) has high energy and power capabilities as they have larger surface area, greater conductivity and also AC has the ability to optimize the properties of supercapacitors. Supercapacitor has gained its attention due to its fast charging/discharging speed, and long-term stability than the normal batteries. In this work, the GO/PANI/AC was synthesized to increase the specific capacitance and the energy storage capability of supercapacitor through modified hummers’ method, in-situ polymerization method and hydrothermal method. Here, the AC was derived from seeds of Ziziphus jujuba and shells of Prunus dulcis . The performances of GO, GO/PANI, GO/PANI/ACZJ, and GO/PANI/ACPD electrodes were evaluated using 6 M KOH as an electrolyte at different current densities and scan rates. The electrochemical properties and impedance of the electrodes were characterized by CV, GCD and EIS analysis to study the suitability of the electrode material. GCD curves of the GO, GO/PANI, GO/PANI/ACZJ and GO/PANI/ACPD composite were analyzed at different current densities such as 1, 2, 4, and 10 A g –1 and observed the high specific capacitance for GO/PANI composite about 234 F g –1 , at 4 A g –1 . The incorporation of PANI supports to improve the specific capacitance in GO/PANI composite. At the same time, the ternary composite exhibited an extremely low specific capacitance. From the GCD curves, the specific capacitance for GO/PANI/ACZJ exhibited 106, 104, 109 and 141 F g –1 and GO/PANI/ACPD showed 31, 34, 39 and 54 F g –1 at current densities of 1, 2, 4, and 10 A g –1 respectively. Even the ternary composite possess low specific capacitance, the observed energy and power density for GO/PANI/ACPD are 25.87 Wh g –1 and 9252.75 W g –1 , respectively and for GO/PANI/ACZJ are 9.94 Wh g –1 and 3556.80 W g –1 . From Nyquist plots, it is observed that R s and R ct of GO/PANI/ACZJ electrode are 33.4 and 30.31 Ω respectively. The better electrochemical performance is probably due to enhanced surface area and high specific capacitance.