Surfactant-assisted electrodeposition and improved electrochemical capacitance of silver-doped manganese oxide pseudocapacitor electrodes

Abstract

Ag-doped MnO2 pseudocapacitor electrodes with dendrite and foam-like structures were successfully produced for the first time using an electrodeposition method employing structure-directing agents, i.e., sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB) acting through micelle formation at solid–liquid interfaces. Doping silver with MnO2 enhanced their electronic conductance. Controlling pseudocapacitor electrode morphologies with surfactants accelerated ion transport. The specific capacitance values of the Ag-doped MnO2 films produced with SDS and CTAB, measured in 0.5 M Na2SO4 at a scan rate of 5 mV s−1 were 551 and 557 F g−1, respectively. These values are about 2.7-fold higher than that of the pure MnO2 film and about 1.4-fold higher than that of the Ag-doped MnO2 film made without using surfactants.