LAUSR

Abstract Manganese dioxide (MnO 2 ) is an ideal electrode material for supercapacitors due to its low cost and large theoretical specific capacity. We reported the hydrothermal synthesis MnO 2 nanostructures with different morphologies through the variation of hydrothermal temperature and dwell time. It was found that cauliflower-like δ-MnO 2 particles are prepared at a lower temperature while the needle-like α-MnO 2 nanorods are formed at a higher temperature. The morphologies of MnO 2 were also affected by the hydrothermal dwell time. The needle-like α-MnO 2 nanorods have the higher specific surface (114 m 2  g −1 ) than that of the cauliflower-like δ-MnO 2 particles. Electrochemical properties were evaluated using cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS). The hierarchical multidimensional MnO 2 architecture nanostructured surface with particles and nanorods, shows a maximum specific capacity (311.52 F g -1  at 0.3 A g −1 ). These results provided a generic guideline in developing different nanostructured electrode materials for electrochemical energy storage.