Effect of Calcination Conditions on the Supercapacitive Performance of Activated Carbon/Nickel Oxide Nanocomposite Electrodes Prepared by Electroless Nickel Plating

Abstract

Electrochemical capacitors or supercapacitors or ultracapacitors have been identified as a promising technology that has a significant role to play in the electrical energy storage device revolution. Electrode material quality plays a crucial a role in defining the performance of the supercapacitor. This study fabricated nanocomposite electrodes from activated carbon and nickel oxide using electroless plating for supercapacitor applications. The electrochemical investigations reveal nanocomposite electrodes having prevalent capacitive performance in comparison to the activated carbon electrode. The specific capacitance, energy density and power density of the prepared composite samples were found to be 228.00–411.52 F g−1, 8.67–14.29 Wh kg−1 and 210.42–476.32 W kg−1, respectively, which signified an increase of 114.92–276.84 F g−1, 3.99–9.61 Wh kg−1 and 29.88–250.68 W kg−1, respectively, with regard to the carbon electrode. Furthermore, reduction in specific capacitance and energy density was observed when calcination temperature and time were increased from 300°C to 500°C and 1 h to 2 h, respectively, suggesting that calcination at an elevated temperature for a lengthy time is detrimental to the electrochemical performance of the nanocomposite electrodes. The nanocomposite electrode calcinated at 300°C for 1 h exhibited the highest improvement of 205% equally in specific capacitance and energy density, while the nanocomposite electrode calcinated at 500°C for 2 h offered the maximum power enhancement of 112%.