工艺参数对熔盐法制备钛酸铋粉体影响的研究

Influences of Processing Parameters on Bi_4Ti_3O_(12) Powder Prepared by Molten Salt Methods

研究了工艺参数对熔盐法制备钛酸铋粉体晶粒形貌和尺寸的影响.发现温度、盐的种类和盐的用量能够较显著地影响晶粒的形貌和尺寸.在氯盐中,晶粒尺寸随着温度的升高而逐渐增大,晶粒最终发育为较规则的圆片状,晶粒生长按照Ostwald液相生长机理来进行.在硫酸盐中,晶粒尺寸明显大于相同条件下在氯盐中的尺寸,且晶粒形貌呈不规则片状.当原料与盐的比例<1时,随着盐用量的增加,晶粒尺寸减小,形貌更加不规则.通过调整工艺参数能够控制颗粒的尺寸和形貌,制备具有各向异性生长的钛酸铋片状粉体.

The influences of processing parameters on Bi4Ti3O12 powder prepared by a molten salt method were studied. The results obtained indicate that the powder characteristics are greatly influenced by the synthesizing temperature, type and quantity of the salts used. In chloride salt, Bi4Ti3O12 particles grow by the Ostwald ripening mechanism, their dimension increases with increasing temperatures, showing a circular platelike morphology. The powder prepared in sulfate salt has larger particle size and more irregular platelike morphology than that in the chloride salt. As the Bi4Ti3O12 precursor to salt ratio is less than 1, the grain size decreases with increasing sulfate salt quantity, at the same time the particle morphology becomes more irregular. Bi4Ti3O12 powder with specific particle size and morphology can be obtained by adjusting the processing parameters.