Controlled Synthesis of Mesoporous MnO₂ Nanospindles

We synthesized mesoporous MnO₂ nanospindles by a one-step hydrothermal process in an aqueous solution of KMnO₄ and glucose. The structure, morphology, purity, and size of the products were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), and nitrogen adsorption/desorption (BET) measurements. The reaction time and concentrations of glucose influenced the final structures and shapes of the MnO₂ nanospindles. The length to diameter ratio of the MnCO₃ precursor nanospindles can be easily tuned from 1.35:1 to 2.89:1. A possible formation mechanism for the mesoporous MnO₂ nanospindles is proposed and discussed.