HNO_3胶溶对Al_2O_3薄膜性能的影响

Effect of HNO_3 peptization on Al_2O_3 membrane properties

以异丙醇铝为前驱体,HNO3为胶溶剂,采用溶胶-凝胶法制备Al2O3膜。考察HNO3浓度对溶胶及薄膜的影响,通过TG-DTG,XRD,AFM,BET等表征手段对溶胶的稳定性及黏度,薄膜的热稳定性,物相组成,表面形貌,微孔结构及分布等进行综合分析。结果表明:随HNO3浓度增大,溶胶黏度增大,HNO3浓度为5 mol/L时溶胶发生团聚;薄膜的热稳定性较好,高于500℃加热薄膜几乎没有质量损失;随烧结温度升高,薄膜中的γ-AlOOH逐渐向γ-Al2O3转变,薄膜因此变得更加稳定;薄膜表面较为平整,微孔分布均匀,平均孔直径为4.22 nm。

Using isopropanol aluminum as precursor, HNO3 as peptizator, Al2O3 membranes were prepared by Sol-Gel method. The effect of concentration of HNO3 on the sol and membrane was studied. A comprehensive analysis of the stability of the sol, the thermal stability of the membrane, phase composition, surface morphology, pore structure and distribution were conducted by characterization means of sol viscosity, TG-DTG, XRD, AFM and BET. The results show that, with increasing concentration of HNO3, sol viscosity increases, reunion appears when HNO concentration is 5 mol/L;Al2O3 membrane has good thermal stability, it almost has no mass loss after 500 ℃; With increasing sintering temperature, γ-AlOOH in the membrane gradually transforms to γ-Al2O3, and membrane becomes more stable; the surface of Al2O3 membrane is relatively smooth, pore distribution is uniform, the average pore diameter is 4.22 nm.