Low dielectric loss and good thermal stability of Eu and Ti co-doped K0.5Na0.5NbO3 ceramics

Research paper by Lanbing Fei, Danping Shi, Yanming Huang, Laijun Liu

Indexed on: 14 Jun '15Published on: 14 Jun '15Published in: Journal of Materials Science: Materials in Electronics


In order to develop dielectric ceramics with temperature-stable permittivity characteristics, Eu and Ti co-doped K0.5Na0.5NbO3 [(1 − x)K0.5Na0.5NbO3-xEuTiO3] ceramics were prepared by a conventional solid state route. The effect of EuTiO3 on the phase structure and dielectric performance of KNN ceramics were investigated. The temperature dependence of the relative permittivity illustrated that the small amount of EuTiO3 depressed the dielectric peak of ferroelectric-paraelectric transition. Therefore, the temperature stability and relative permittivity of ceramics were effectively improved. As x = 0.03, the ceramic showed superior dielectric temperature stability (±10 %), very low dielectric loss (0.008 at 250 °C) and a relatively high permittivity (>1500 at 250 °C) over the temperature range from ~100 to 350 °C. It suggests that this ceramic is a promising candidate for high-temperature capacitor application.