Study of the dielectric responses of Eu-doped CaCu3Ti4O12

We reported the effect of europium (Eu) on the dielectric properties of CaCu3Ti4O12 (CCTO). The experimental results show that the doping of Eu on a calcium (Ca) site improves the dielectric loss and decreases the dielectric constant of CCTO. To understand the underlying reasons for the depressed dielectric response of Eu-doped CCTO, scanning electron microscopy, high-temperature dielectric measurement, and complex impedance measurement were carried out. The DC bias was also used in the measurements. The results show that the depressed dielectric responses of Eu-doped CCTO may be related to the lack of the oxygen vacancies in the samples. Furthermore, the absence of the electrode contact response may be another factor responsible for the decreased dielectric constant.