摘要
采用化学共沉淀─超临界干燥技术制备ＣａＯ－ＺｒＯ２纳米粉体，并详细考察了主要制备参数──共沉淀过程的ｐＨ值对产品粉体性能的影响。实验表明，超临界流体干燥法能很好地保留初始湿凝胶的结构，有效地防止凝胶干燥过程中粒子间硬团聚现象的发生，该法合成的纳米粉体具有粒径小、粒度分布范围窄、比表面大等特点；此外，实验还发现，水合凝胶体系的ｐＨ值会很大程度上影响产品粉体的性能，在实验范围内，随着体系ｐＨ值的增大，粉体的粒径逐渐减小，粉体中单斜相（ｍ）的含量降低，四方相（ｔ）及立方相（ｃ）的含量逐渐升高。
Coprecipition-supercritical fluid drying(SCFD)method is used for the synthesis of CaO-stabilized ZrO2 ultrafine powders, and the effects of pH value in coprecipition on properties of produced grain are also investigated.The results show that SCFD can improve effectively the aggregation behaviour of grains during the gel drying process,and the ultrafine powder obtained by this method has little grain size,good monodispersibility and high surface area.In this experimental scope, with the increase of pH value,the particle size decreases and the contents of t-Zro2 and c-ZrO2 get higher.
基金
国家自然科学基金
关键词
复合氧化物
制备
超细粉末
纳米材料
aO-stabilized ZrO_2
ultrafine particle
supercritical fluid drying
gel structure
