Enhanced dielectric properties and electrical responses of cobalt-doped CaCu3Ti4O12 thin films

作者：Xu Dong^*; Yue Xianning; Zhang Yudong; Song Juan; Chen Xiang; Zhong Sujuan; Ma Jia; Ba Li; Zhang Lei; Du Sanming

来源：Journal of Alloys and Compounds, 2019, 773: 853-859.

DOI：10.1016/j.jallcom.2018.09.340

• Thin films
• Sol-gel
• Dielectric constant
• Dielectric loss
• Nonlinear coefficient

This work firstly reported preparation of cobalt-doped CaCu3Ti4O12 (CCCTO) thin film by a sol-gel modified method. It was concluded that a relatively high dielectric constant epsilon' (2326, at 1 kHz), low dielectric loss tan delta (0.012, at 1 kHz) and high nonlinear coefficient proportional to (4.9) were simultaneously obtained in the CaCu2.95Co0.05Ti4O12 thin film at room temperature. The decrease of the dielectric loss was associated with the increase in the density of the insulating grain boundary layer, which was governed by the grain size reduction and densification of CCCTO films due to Co doping. Monovalent cation Cu(+ )detected by X-ray photoelectron spectroscopy (XPS) of the CaCu2.95Co0.05Ti4O12 thin film decreased leakage current. These excellent electrical properties provided a viable solution to the application of CCTO materials in capacitive-varistors.

• 单位
  河南大学; 安徽工业大学; 江苏大学; 郑州大学; 郑州机械研究所