Synthesis and characterization of superfine nanostructure manganese dioxide spontaneously coated onto carbon nanotubes

Abstract

Manganese dioxide nanostructered (MnO2) was coated onto carbon nanotubes (CNTs) by simple immersion of the CNTs into a KMnO4 aqueous solution. The morphology of the CNTs before and after MnO2 deposition was examined using field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM). The superfine coral-like MnO2 deposited and fully covered on the CNTs surface at pH 8. At pH 2 and 6 the MnO2 deposited as the superfine nanorod structure. The superfine MnO2 phase was identified as Birnessite-type MnO2 by X-ray powder diffraction and FESEM. The thermal stability of the superfine nanostructure MnO2 coated CNTs is increase based on the TGA with the weight loss of 4% at 400°C to 900°C.