通过熔盐法,以NaNO3为熔盐介质制备纯相BaMoO4微晶.考察合成温度、反应时间及熔盐含量对产物结晶度、粒径及形貌的影响.采用X线衍射仪(XRD)和扫描电子显微镜(SEM)对微晶进行表征.结果表明:在各种反应条件下都能得到纯的四方相白钨矿结构BaMoO4微晶,且结晶性良好.合成温度及反应时间对产物的形貌有明显影响,随着合成温度的升高和反应时间的延长,晶粒尺寸分布缩小,形貌规整且呈类八面体.熔盐含量对BaMoO4微晶尺寸影响显著,随着熔盐含量增多,晶粒的平均尺寸缩小.制备形貌规整且尺寸较小的BaMoO4微晶适宜条件为NaNO3与Na2 MoO4的摩尔比=10∶1时在500℃下保温4h.%Pure BaMoO4 microcrystals were synthesized through molten salt method with NaNO3 as reaction media. The effects of the temperature, soaking time and amount of molten salt on the crystallinity, particle size and morphology of product were investigated. Characterization techniques, such as X-ray diffrac-tometer (XRD) ,and scanning electron microscope (SEM) , were used to analyze the products. Results showed that BaMoO4 microcrystals with pure tetragonal phase scheelite structure and excellent crystallinity were obtained under several conditions. Temperature and soaking time obviously affected the morphology of products. With prolonging time and elevating temperature, size distribution shrank and particles had a well-defined shape, similar to octahedron. The optimal conditions for BaMoO4 microcrystals with well-defined morphology and high crystallinity from molten salt synthesis were 500 ℃ for 4 h with 10:1 molar ratio of NaN03 to Na2MoO4.
展开▼
