【摘要】 以异丙醇铝为主要原料采用溶胶-凝胶法制备纳米氧化铝粉体。利用TG/DTA、XRD、TEM等测试手段研究醇铝水解时不同的加水方式对纳米氧化铝粉体的形成过程和显微结构的影响。结果表明,加水方式影响着醇铝水解产物的晶态和形貌,进而影响着最终产物纳米氧化铝粒子的形貌。采用喷水方式加水得到的水解产物为团絮状的非晶体,采用喷雾加水方式得到的醇铝水解产物针状的勃姆石AlOOH。分析认为这主要是由于加水方式影响着溶液的过饱和度,从而影响着晶核的形成。先驱体的结构影响着氧化铝粉体的结构,团絮状的非晶体煅烧后获得球状氧化铝粉体,针状的水解产物煅烧后形成了片状γ-Al2O3粉体。更多还原

【Abstract】 The nano-sized alumina powders were fabricated using aluminum alkoxides as main raw materials by sol-gel method. The influence of the way of water addition on the forming process and the morphology of nano-sized Al2O3 powders was studied by TG/DTA, XRD and TEM. The results show that the way of water addition influenced the crystal style and morphology of the hydrous products and the nano-sized alumina powders. The hydrous products synthesized by the way of water addition are quasi-spheroidal amorphous substances, while the hydrous products synthesized by the way of vapor addition are acicular crystal AlOOH. It is considered that the way of water addition affected the supersaturating ability of the solutions. The structure of the precursor affected the structure of the nano-sized alumina powders. Spherical Al2O3 powders are obtained from quasi-spheroidal amorphous precursor, while flake-like Al2O3 powders are obtained from acicular precursor.更多还原