Simple hydrothermal preparation of γ-MnOOH nanowires and their low-temperature thermal conversion to β-MnO2 nanowires

Without the use of any extra surfactant or template, gamma-MnOOH single crystalline nanowires were synthesized directly through the hydrothermal reaction between KMnO4 and toluene in distilled water at 180 degrees C for 24h; and beta-MnO2 single crystalline nanowires could be obtained just by calcination of the gamma-MnOOH nanowires in air at 280 degrees C for 5 h. The as-prepared gamma-MnOOH and beta-MnO2 nanowires were characterized by X-ray powder diffraction, atomic absorption spectroscopy, Fourier transformed infrared spectroscopy, scanning electron microscope, transmission electron microscope, high-resolution transmission electron microscope and selected area electron diffraction. (c) 2005 Elsevier B.V. All rights reserved.