Sol-gel synthesis and characterization of nanocrystalline (Bi0.5Na0.5)TiO3 powders from the poly vinyl alcohol evaporation route
Nanocrystalline pure perovskite phase bismuth sodium titanate ((Bi0.5Na0.5))TiO3(BNT) powders have been prepared by a sol-gel method from the poly vinyl alcohol evaporation route, bismuth nitrate Bi(NO3)3, tetra-butyl titanate Ti(OC4H9)4 and sodium acetate(CH3COONa) were used as raw materials and poly vinyl alcohol(PVA) as the sol-gel forming solvent. Stoichiometric amounts of the individual raw materials were thoroughly mixed in accordance with the BNT composition to form the stock solution. The pH of the stock was adjusted to 1-3 by adding acetate. Aqueous solution of PVA10%(w/v) was then added to the cationic mixture with thorough stirring. The weight ratio of the canonic mixture to the PVA aqueous solution was maintained at 2∶1. The resulting viscous liquid was then heated over a hot crucible up to form a fluffy dry gel. The fluffy dry gels were calcined at different temperatures and times and then cooled to room temperature naturally. The X-ray powder diffraction(XRD) patterns of the heat-treated powders were obtained using a Broker D8 Advance X-ray diffractometer with Cu Ka radiation and nickel filter. Scanning electron microscope (SEM) studies of the NBT powders were performed using a JSM-6700F electron microscope. Phase-pure BNT powders were obtained at 550℃ for 2-2.5h which is relatively lower calcination temperature than other reports. The BNT powders consists of phase-pure perovskite nanocrystals with an average size of 100-200nm.
Liu Haitao Wang xiaohui Li Longtu
College of Chemistry and Material Engineering,Wenzhou University,Wenzhou,325035 P.R.China State Key State Key Laboratory of New Ceramics and Fine Processing,Department of Material Science and Engineer
国际会议
The 8th China International Nanoscience and Technology Symposium(2009第八届中国国际纳米科技湘潭研讨会Cinsts09)
湖南湘潭
英文
1-5
2009-10-23（万方平台首次上网日期，不代表论文的发表时间）