Controllable synthesis of beta-Mn2V2O7 microtubes and hollow microspheres

beta-Mn2V2O7 microtubes with the range of 15-25 mu m in length, 2.5-3.5 mu m in external diameter, and ca 0.4 mu m of the wall in thickness, as well as beta-Mn2V2O7 hollow microspheres with an average outer diameter of 2 mu m were successfully synthesized in a suitable molar ratio of NH4VO3 and MnCO3 powders via a hydrothermal process. XRD and FESEM were used to characterize the products, and the magnetic susceptibility curve was also measured. In the whole process, the concentration of Mn2+ cations derived from MnCO3 dissolution plays a crucial role in the formation of beta-Mn2V2O7 microtubes and hollow microspheres. (C) 2008 Elsevier B.V. All rights reserved.