Preparation and structure characteristics of nano-Bi2O3 powders with mixed crystal structure
来源期刊:中南大学学报(英文版)2005年第3期
论文作者:李卫
文章页码:243 - 245
Key words:nano- Bi2O3 powders; chemical precipitation method; mixed crystal structure
Abstract: The nano- Bi2O3 powders were prepared by a chemical precipitation method with Bi(NO3) 3, HNO3 and NaOH as reactants. The structural characteristics and morphology of nano- Bi2O3powders were investigated by X-ray diffraction and transmission electron microscopy, respectively. The results show that under the optimum condition that 300 g/L Bi(NO3) 3reacts at 90℃for 2 h, the Bi2O3 powders with 60 nm on the average and 99.5% in purity are obtained. The prepared nano- Bi2O3powders contain a mixed crystal structure of monoclinic and triclinic instead of traditional structure of monoclinicα- Bi2O3. And the mixed crystal structure is stable in air. The reason for the appearance of the mixed crystal structure may be that the ionic radius ratio of Bi3+to O2- changes easily during the formation of nano- Bi2O3 particles by a chemical precipitation method.