Cyclic voltammetrically prepared MnO2-PPy composite material and its electrocatalysis towards oxygen reduction reaction (ORR)

A composite material containing manganese dioxide and polypyrrole (denoted as MnO2-PPy) was successfully fabricated onto a graphite substrate by cyclic voltammetry (CV) technique from a 0.5 M H2SO4 solution having 0.2 M pyrrole (Py) and 0.2 M MnSO4. Results obtained from cyclic voltammograms (CVs) and charge-discharge curves demonstrated that this composite material can be utilized as a satisfied supercapacitance material due to its excellent charge-storage ability and reversibility of charging-discharging. Scanning electron microscopy (SEM) images revealed that more packed materials were obtained when MnO2 was formed among polypyrrole. And for the first time, this composite was employed to ORR, and results obtained from CVs demonstrated that this composite has electrocatalysis towards ORR in an acid solution of 0.5 M H2SO4 when compared to the pure PPy. (c) 2009 Elsevier B.V. All rights reserved.