纳米γ-Al_2O_3的溶胶-凝胶法制备及表征(英文)

Preparation and Characterization of Nanocrystalline γ-Al_2O_3 by Sol-Gel Process

异丙醇铝为先驱体，异丙醇为溶剂，乙酰乙酸乙酯为螯合剂，聚乙二醇（PEGl000）为分散剂，硝酸为胶溶剂，采用溶胶一凝胶法制备了纳米γ-Al2O3。并采用DTA／TG,XRD，TEM等测试技术对纳米γ-Al2O3粉体进行表征。结果表明，通过溶剂、螯合剂、分散剂和胶溶剂的协同效应，在750℃煅烧条件下，γ-Al2O3粒子形貌为针状结构，长度为20-30nm：在900℃煅烧条件下，γ-Al2O3粒子形貌为颗粒状，平均晶粒尺寸为10nm左右；纳米γ-Al2O3粒子尺寸均一、分散性良好。

With aluminum isopropoxide （Al（OC3H7i ）3 ） as precursor, isopropyl alcohol （ C3H7OH ） as solvent, ethyl acetoacetate （etac） as chelating agent, polyethylene glycol （ PEG1000 ） as dispersant, HNO3 as peptizing agent, the nanocrystalline γ-Al203 powders were prepared by sol-gel process. The characteristics of the powders were investigated by differential thermal analysis （DTA） and thermogravimetric analysis （TG）, X-ray diffraction （XRD） and transmission electron microscope （TEM）. The results show that the as-prepared γ-Al2O3 particles are needle-like with the length of about 20-30 nm at the calcined temperature of 750 ℃, become grain-like with the size of about 10 nm at 900 ℃, and the γ-Al2O3 particles are well uniform and dispersive.