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利用固相扩散法在1 450℃下制备了YAl O_3粉末样品和陶瓷片样品,并在不同温度和不同气氛(air,O_2or N_2)下对样品进行退火处理调制了其缺陷浓度。基于漫反射光谱和交流阻抗谱分析了YAl O_3样品的体色与其缺陷浓度之间的关系。研究结果表明YAl O_3具有p型导电机理,其浅棕色体色是由阳离子空位引起的。在高温和氮气氛下处理该材料其缺陷浓度减少,体色变浅。第一性原理计算结果认为YAl O_3中的主要缺陷应该是铝空位V_(Al~×)。
YAl O_3 powder samples and ceramic samples were prepared by solid phase diffusion method at 1 450 ℃. The samples were annealed at different temperatures and different atmospheres (atmosphere, O_2or N_2) to prepare the defect concentration. The relationship between the color of YAl O 3 sample and its defect concentration was analyzed based on diffuse reflectance spectra and AC impedance spectra. The results show that YAl O_3 has a p-type conduction mechanism and the light brown body color is caused by cationic vacancies. The material is treated at elevated temperatures and under a nitrogen atmosphere with reduced defect concentrations and lighter body colors. The first-principle calculations show that the main defect in YAl O 3 should be the aluminum vacancy V_ (Al ~ ×).