Electrochemical performance of activated carbons/Mn₃O ₄-carbon blacks for supercapacitor electrodes

In this work, manganese dioxide (Mn₃O₄)/carbon black (CB) composites (Mn-CBs) were prepared by an in situ coating method as electrical fillers and the effect of the Mn-CBs on the electrical performance of activated carbon (AC)-based electrodes was investigated. Structural features of Mn-CBs produced via in situ coating using a KMnO4 solution were confirmed by XRD and TEM images. The electrical performances, including cv curves, charge-discharge behaviors, and specific capacitance of the ACs/Mn-CBs, were determined by cyclic voltammograms. It was found that the composites of Mn ₃O₄ and CBs were successfully formed by in situ coating method. ACs/Mn-CBs showed higher electrical performance than that of AC electrodes fabricated with conventional CBs due to the pesudocapacitance reaction of manganese oxides in the aqueous electrolyte. Consequently, it is anticipated that the incorporation of Mn₃O₄ into CBs could facilitate the utilization of CBs as electrical filler, leading to enhanced electrochemical performance of AC electrodes for supercapacitors.