Dielectric relaxation in double perovskite oxide, Ho2CdTiO6

Bulletin of Materials Science

关键词: Holmium cadmium titanate;    double perovskite;    dielectric relaxation;    impedance spectroscopy.;   

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

A new double perovskite oxide holmium cadmium titanate, Ho2CdTiO6 (HCT), prepared by solid state reaction technique is investigated by impedance spectroscopy in a temperature range 50–400°C and a frequency range 75 Hz–1 MHz. The crystal structure has been determined by powder X-ray diffraction which shows monoclinic phase at room temperature. An analysis of complex permittivity with frequency was carried out assuming a distribution of relaxation times as confirmed by Cole–Cole plot. The frequency dependent electrical data are analysed in the framework of conductivity and electric modulus formalisms. The frequencies corresponding to themaxima of the imaginary electric modulus at various temperatures are found to obey an Arrhenius law with an activation energy of 0.13 eV. The scaling behaviour of imaginary part of electric modulus suggests that the relaxation describes the same mechanism at various temperatures. Nyquist plots are drawn to identify an equivalent circuit and to know the bulk and interface contributions.

【 授权许可】

CC BY