Hydrothermal vs electrodeposition: How does deposition method affect the electrochemical capacitor performance of manganese dioxide?

Hydrothermal and electrodeposition are widely utilized methods in the preparation of MnO2 nanomaterials for electrochemical capacitor application. In this paper, these two approaches were applied to synthesize nanoscale MnO2, and their electrochemical properties were fully investigated in different electrolyte environments. Because of different mechanisms, the hydrothermal method gave an ultrathin layer of MnO2 nanosheets with a large accessible electrochemical surface area, while the electrodeposition method resulted in the formation of MnO2 nanorods with a rather limited opening area. The electrochemical performance of hydrothermally prepared MnO2 was much better in specific capacitance and overall resistance, except the cycling durability, as a result of its unique structure.