Cathodic electrodeposition of Ag-doped manganese dioxide films for electrodes of electrochemical supercapacitors

Cathodic electrodeposition method has been developed for the fabrication of Ag-doped MnO(2) films from the KMnO(4) aqueous solutions containing AgNO(3) for the application in electrodes of electrochemical supercapacitors (ES). The films were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), cyclic voltammetry (CV) and impedance spectroscopy. The Ag-doped MnO(2) films showed improved capacitive behaviour and lower electrical resistance compared to pure MnO(2) films. The highest specific capacitance (SC) of 770 F g(-1) was obtained at a scan rate of 2 mV s(-1) in the 0.5 M Na(2)SO(4) electrolyte. (C) 2011 Elsevier B.V. All rights reserved.