化学沉淀法制备纳米钛酸镁粉体

以TiCl₄和MgCl₂混合液为原料液、NaOH为沉淀剂，采用化学沉淀法制备纳米钛酸镁粉体。考察了沉淀剂浓度、原料液中Mg²⁺与Ti⁴⁺的摩尔比、煅烧温度等因素对目的产物颗粒大小和晶型的影响;采用透射电镜和X射线衍射等多种分析测试方法对制得粉体进行了表征。实验结果表明：当镁钛混合液中的Mg²⁺与Ti⁴⁺的摩尔比为1.2（固定钛离子浓度为0.5mol/L）、沉淀剂NaOH浓度为6mol/L、反应温度98℃、镁钛混合液与NaOH溶液的体积比为1:1、煅烧温度为800℃时，制备出了平均粒径约为55nm、结晶度好、形貌为球形的纳米钛酸镁粉体。

Synthesis of nano-sized magnesium titanate powders by chemical-reactive precipitation

Nano-sized magnesium titanate powders was prepared by a chemical-reactive p recipitation method, in which the mixture solution of MgCl₂ and TiCl₄ acted as the starting material and NaOH as precipitant, respectively. The effects of the concentration of NaOH solution, Mg²⁺ and Ti⁴⁺ molar ratio in the starting reactant and the calcining temperature on the particle size and p hase composition of magnesium titanate were studied. The magnesium titanate powd ers obtained were characterized by using XRD, TG, DSC and TEM. The experimental results show that the feasible conditions for the synthesis of MgTiO₃ powders are as follows: the concentration of the precipitant is 6mol/L, the volume rat io of the mixture solution to the NaOH solution 1:1, the Mg²⁺/Ti⁴⁺ molar ratio 1.2:1, with the reacting temperature at 98℃, and the ordered he xagonal MgTiO3 powders with a mean particle size of 55nm are obtained by cal cined at 800℃.