Manganese dioxide–carbon nanotube nanocomposites for electrodes of electrochemical supercapacitors

Electrodes for electrochemical supercapacitors were fabricated by cathodic electrodeposition of MnO2 on carbon nanotubes (CNTs), which were grown by chemical vapour deposition on stainless steel meshes. The MnO2–CNT nanocomposites were characterized by scanning electron microscopy, transmission electron microscopy, cyclic voltammetry and impedance spectroscopy. The electrodes showed excellent capacitive behaviour in the 0.5 M Na2SO4 electrolyte, with specific capacitance of 356 F g−1 at a scan rate of 2 mV s−1.