Self-assembled flower-like hierarchical spheres and nanobelts of manganese oxide by hydrothermal method and morphology control of them

Self-assembled 3D flower-like hierarchical spheres composed of small nanosheets and nanobelts of manganese oxide were prepared by a simple hydrothermal method at 125 degrees C and 200 degrees C, respectively in aqueous solution, without the assistance of any templates and SDAs. A mechanism involving two competitive factors, temperature and Coulomb interaction, was proposed to understand their formation. Morphology control of the product can be easily achieved by adjusting the reaction temperature according to this mechanism, which was supported by other parallel experiments. The product was characterized by XRD, TEM, FESEM and BET surface area analysis was also carried out. (C) 2007 Elsevier B.V. All rights reserved.