Hydrothermal synthesis of -MnOOH nanowires and - MnO2 sea urchin-like clusters

γ -MnOOH nanowires and α - MnO2 sea urchin-like clusters have been selectively synthesized in two oxidation systems via a facile hydrothermal route. The γ -MnOOH nanowires were obtained from MnSO4 in the presence of H2O2 as an oxidizer in an alkaline solution, while the α - MnO2 sea urchin-like clusters were formed from MnSO4 in the presence of K2Cr2O7 as an oxidizer in an acid solution.