YSZ薄膜的溶胶凝胶法制备及其电导性能

THE PREPARATION OF YSZ FILMS BY SOL GEL METHOD AND THEIR ELECTRICAL CONDUCTIVITY

应用溶胶凝胶方法制备了ＹＳＺ薄膜。通过ＸＲＤ，ＳＥＭ和低频阻抗分析仪等分析手段，研究了ＹＳＺ薄膜的相结构、形貌特征及其电导性能。结果表明：应用溶胶凝胶方法制备的ＹＳＺ薄膜经８００℃以上热处理后形成完整的立方相结构。随着烧结温度的升高，薄膜表面变得致密，气孔明显减少。至１０５０℃时，薄膜表面光滑，无裂纹，无针孔，圆球形的小颗粒均匀分布。薄膜与衬底的结合紧密，薄膜厚度均匀，膜厚约为１．０μｍ。阻抗谱分析结果表明：ＹＳＺ薄膜的阻抗谱是一个完整的半圆，圆心稍低于实轴。在１００～１０００℃温度范围内，ＹＳＺ薄膜的电导率随着温度的升高而增加，且Ａｒｒｈｅｎｉｕｓ曲线在２８０℃和５００℃处分别出现两次转折。

YSZ films are prepared by sol gel method. The phase structure, microstructure and electrical conductivity of YSZ films are studied by using XRD, SEM and LF(low frequency)impedance meter. The results show that the YSZ films prepared by sol gel method must be calcined at a temperature above 800℃ in order to form perfectly cubic phase structure. The film surface densifies and pores decrease with the increase of heating temperature.At 1050℃, the film surface becomes smooth, free of cracks and pores, and the spherical grains distribute uniformly. The film and substrate combine firmly,the thickness of film is about 1.0 μm. Impedance spectra analysis shows that the impedance spectra of YSZ films are well defined semicircles with the center below the real axis. The conductivity increases with the testing temperature increasing in the range between 100℃ and 700℃, and the slope of Arrhenius curve varies twice at 280℃ and 500℃.