Hence, with the aim of combining the advantages of MnO2 as a pseudocapacitive material with the unique characteristics of hydrothermal technique to fabricate interesting nanostructures of MnO2 with excellent electrochemical properties, our main task is to study the changes of morphology and phase composition in different reactant concentrations and by adding of surfactant; meanwhile, the electrochemical properties of
MnO2 electrode material in different morphologies will be comparatively explored. The chemical reaction can be formulated as