Electrochemical Performance of Fabricated Supercapacitors Using MnO2/Activated Carbon Electrodes

Abstract

Peanut shells were subjected to pyrolysis and chemical activation to produce activated carbon with high specific surface area. MnO₂ particles was synthesized on the activated carbon surface. Supercapacitors were fabricated by using activated carbon electrodes and tested by constant current charge-discharge, self-discharge, and life-cycle tests. MnO₂ loading led to a significant decrease in specific surface area. The pore volume distribution calculations revealed that the MnO₂ particles were in nanometer size. Because of the reduction of ions to MnO₂ over the activated carbon surface, the amount of oxygen-containing surface functional groups changed. Although the MnO₂ loading caused a decrease in surface area, the specific capacitance increased from 49 F/g to 68 F/g.