The dielectric constant of CaCu3Ti4O12 ceramics

3^rd International Conference and Expo on Ceramics and Composite Materials

June 26-27, 2017 Madrid, Spain

C P Yang, X Y Luo, D W Shi, H B Xiao, L F Xu and K Barner

Hubei University, PRC
University of Gottingen, Germany

Posters & Accepted Abstracts: J Material Sci Eng

Abstract :

After the discovery of a gaint permittivity in CaCu3Ti4O12 by Subramanian et al. in 2000, extensive investigations to explore the origin have been performed in recent years. CaCu3Ti4O12 is a perovskite-like compound with a dielectric constant up to 105, which is almost temperature independent from 100 K to 400 K and shows neither ferroelectric phase nor crystallographic structural transition. These unusual properties are very valuable for practical applications. However, the source of the giant dielectrical constant is not clear. In this work, the dielectric properties of CaCu3Ti4O12 ceramics were studied using AC and DC electrical measuring methods in order to understand the origin of the colossal dielectric constant, including impedance spectra analysis, frequency and temperature spectrum, electrical conditioning treatment and capacitance � biased voltage curves measuring. The experimental results indicate that the constant is very strongly correlated with defects in CaCu3Ti4O12, especially oxygen vacancy, which is the main contribution for the dielectric polarization at low frequencies and high temperatures.

Biography :

Email: cpyang@hubu.edu.cn