Electrochemical Performance of MnO₂/C Electrodes in Neutral Aqueous Electrolytes

The surface of carbon electrodes has been modified by manganese oxide nanoparticles via anodic electrochemical deposition. The structural properties and elemental composition of the resultant MnO₂/C materials have been studied by energy dispersive X-ray microanalysis and transmission electron microscopy. Electrochemical characteristics of the electrodes have been investigated by cyclic voltammetry, galvanostatic charge–discharge measurements, and impedance spectroscopy. We have compared the specific capacitance of the MnO₂/C electrodes in 0.5 M Li₂SO₄, Na₂SO₄, and K₂SO₄ solutions. The materials studied have been shown to have the highest specific capacitance in the sodium sulfate solution.