Preparation and Enhanced Electrochemical Performance of MnO2 Nanosheets for Supercapacitors

Abstract MnO 2 nanosheets have been synthesized by using a redox reaction of manganese nitrate tetrahydrate and potassium permanganate without any surfactants. The morphology and microstructure of the as‐prepared material were characterized by field emission scanning electron microscopy, transmission electron microscopy and X‐ray diffraction (XRD). Electrochemical performances as electrode materials for supercapacitor were evaluated using cyclic voltammetry and galvanostatic charge‐discharge in 1 M Na 2 SO 4 aqueous electrolyte. It was found that MnO 2 nanosheets showed an excellent capacitive behaviour with good cycling stability. The specific capacitance of the MnO 2 nanosheet electrode can reach up to 332.8 Fg −1 at a current density of 500 mA/g and a stable cycling performance.