溶胶-凝胶法制备纳米BaTiO3粉体的影响因素

溶胶－凝胶法是制备纳米粉体的一种重要方法．本文以BaTiO₃纳米粉体的制备为例，系统地考察了溶剂、加水量、陈化时间和锻烧温度对粉体的形成过程和显微结构的影响．发现不同的溶剂类型能够改变胶凝时间，加水量的多少会影响醇盐水解缩聚物的结构，陈化时间的长短直接改变晶粒的生长状态，煅烧温度的变化对粉体的相结构和晶粒大小有重要的作用．通过研究反应过程的物理化学变化并优化制备工艺，得到了晶粒小、分散性好、低团聚的BaTiO₃纳米粒体．

Influential Parameters for Preparing Nanostructured BaTiO3 Powder by Sol-gel Method

Sol-gel procedure is an important method on the fabrication of nanocrystalline powders. In present paper, we studied the influences of some parameters, including the type of solvent, amount of water addition, ageing time and calcination temperature on the properties of BaTiO₃ powder. It was found that the solvent type affected the gel point, the different amount of water addition could alter the structure of condensation polymer, the varying of ageing time influenced the growth of grains and the calcination temperature had great effect on phase structure and grain size. Studying the physical and chemical changes during the reactions, we obtained nanocrystalline BaTiO₃ powders with fine grain size, low aggregates and fine grain distribution.