摘要
离子交换法制得V_2O_5凝胶和SiO_2含量低于50％(mol)的SiO_2-V_2O_5凝胶。借助透射电镜和电子衍射仪,研究了凝胶的结构,并用DTA-EGA和XRD分析了热处理过程中凝胶的物理化学变化。浸涂法制得V_2O_5和SiO_2-V_2O_3导电膜。凝胶具纤维状结构并含有V_2O_5·H_2O晶子。热处理温度影响膜的状态和电导率。电导率随温度升高,在305～315℃达最大值0.3 Ω^(-1)cm^(-1),温度进一步提高时将导致V_2O_5晶化和电导率下降。SiO_2的掺入提高膜的抗划伤强度并阻缓V_2O_5晶化,但是降低了电导率。
V_2O_5 gel and SiO_2-V_2O_5 gels (SiO_2<50％(mol)) were prepared by ion exchange process. Their textures were studied by TEM and electron diffraction, and the physical and chemical changes during heat treatments were analysed, by DTA-EGA and XRD. Conducting coatings were deposited by dip coating. The gels possess fibrous textures and contain V_2O_5.H_2O crystallites. The morphology and conductivity of coatings are influenced by the temperature of the heat treatment. With increasing temperature, the conductivity of coatings increases and reaches the maximum 0.3 Ω^(-1)cm^(-1) at 305～315℃. However the further increase in temperature leads to the crystallization of V_2O_5 and the decrease in conductivity. With the addition of SiO_2, the scratch hardness of coatings increases and the crystallization of V_2O_■ is retarded, but the conductivity of coatings decreases.
基金
国家自然科学基金
关键词
电导率
制备
导电薄膜
V_2O_5gel
electrical conductivity
ion exchange process
dip coating
V_2O_5conducting coatings
SiO_2-V_2O_5 conducting coatings
