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借助晶界调控和修饰可以提高和改善氧离子导体YSZ的电导率。本文采用射频磁控溅射工艺在单晶Al2O3(0001)衬底上制备了厚度约为2μm具有柱状晶结构特征的氧化钇稳定氧化锆(YSZ)涂层,利用溶胶涂覆工艺在涂层表面涂覆含Fe、Co、Si等元素的扩散源,在一定温度下进行热扩散处理使上述离子沿晶界扩散,研究不同离子的引入对YSZ涂层电导率的影响。溶胶前驱体粉末的TG-DSC分析确定了涂覆处理后的热扩散处理工艺,采用XRD、SEM以及TEM对涂层以及溶胶的形貌、结构和物相进行了测试,采用直流四探针法和交流阻抗谱法对涂层热扩散处理前后的电导率进行了测试。结果表明制备态以及溶胶扩散后的YSZ涂层均具有立方萤石型结构,晶粒大小在50~100nm之间。电导率测试结果表明单独引入Si4+的样品电导率相比于制备态降低了3倍,在此基础上再引入Fe~(3+)的样品电导率相比于制备态提高了3倍,单独引入Co2+的样品电导率变化不大。Fe溶胶扩散后YSZ涂层电导率提高的原因可推断为Fe2O3对晶界处SiO_2的清除作用。
With the grain boundary control and modification can improve and improve the oxygen ion conductor YSZ conductivity. In this paper, a yttria-stabilized zirconia (YSZ) coating with a columnar crystal structure with a thickness of about 2μm was prepared on a single-crystal Al2O3 (0001) substrate by radio-frequency magnetron sputtering. The sol- Coated with Fe, Co, Si and other elements of the diffusion source, at a certain temperature for thermal diffusion diffusion above the grain along the grain boundary to study the different ions introduced YSZ coating conductivity. TG-DSC analysis of the sol precursor powder confirmed the thermal diffusion treatment process after the coating treatment. The morphology, structure and phase of the coating and the sol were tested by XRD, SEM and TEM. The DC four-probe method And AC impedance spectroscopy were used to test the conductivity of the coating before and after thermal diffusion. The results show that the YSZ coatings prepared in the as-prepared state and the sol have a cubic fluorite structure with a grain size of 50-100 nm. Conductivity test results show that the conductivity of the sample introduced Si4 + alone compared to the prepared state decreased by 3 times, on the basis of which the conductivity of the sample Fe 3+ compared to the preparation of state increased by 3 times, separately introduced Conductivity of Co2 + samples did not change much. The reason for the increase of the electrical conductivity of the YSZ coating after the Fe sol is diffused can be inferred as the scavenging effect of Fe2O3 on the grain boundary SiO2.