Fabrication and characterisation of MnOOH and β-MnO₂nanorods with rectangular cross-sections

MnOOH nanorods with rectangular cross-sections have been successfully prepared in high yield via a hydrothermal reduction process at a low temperature. After the subsequent heat treatment of the as-prepared MnOOH nanorods at 350°C for 6 h in air, β-MnO2 nanorods with rectangular cross-section that retained the similar morphologies of MnOOH nanorods were obtained. The products were characterised by powder X-ray diffraction and field-emission scanning electron microscopy. The influences of different degrees of pH on the morphology and phase of the final products under hydrothermal conditions are discussed.