Synthesis of MnO2 particles under slow cooling process and their capacitive performances

The focus of this work is to investigate the capacitive cycle behaviour of MnO2 particles deposited on stainless steel foil after slow and fast cooling processes as electrode candidate material in redox supercapacitors using charge/discharge and cyclic voltammetry at different scan rates. XRD results have proven the formation of MnO2 particles. SEM and TEM are also employed to characterise the nature of produced particles, which confirm that a spherical and flower-like nanostructure of MnO2 was obtained after fast and slow cooling processes. A specific capacitance of 180 F g(-1) is obtained at a scan rate of 1 mV s(-1) in 0.5 M KOH aqueous electrolyte. The proposed electrode shows excellent long-term cyclic stability while maintaining a small internal resistance. (C) 2013 Elsevier B.V. All rights reserved.