Synthesis of Sm3+ doped nano ceria with compositionally tuneable conductivity and dielectric properties

• Published in: Materials research express 2019-03, Vol.6 (3)
• Main Authors: Hemantha Reddy, M V, Sreenivasulu Reddy, T, Hari Krishna, R, Nagabhushana, B M, Chandraprabha, M N
• Format: Article
• Language: English
• ISSN: 2053-1591
• DOI: 10.1088/2053-1591/aaf591

In this paper, we show the influence of samarium, Sm3+ (0-10 mol%) on the dielectric and conductivity properties of solution combustion derived nano ceria (CeO2). The phase formation and microstructural analysis are carried out by powder x-ray diffraction and Raman spectroscopy techniques. The surface morphology and size of the nano CeO2 are evaluated by scanning electron microscopy and transmission electron microscopy (TEM). The dielectric and conductivity studies for different Sm3+ doped ceria samples are carried out at varying wide range of frequencies (20 Hz-10 MHz) and temperature (200 °C-800 °C). We show that with increase in Sm3+ concentration the dielectric constant increases and there is considerable decrease in the dielectric loss. This variation in the conductivity with varying dopant concentration is explained by the oxygen vacancies created and their interaction with different defects in the lattice. The conductivity variation indicates Arrhenius behaviour in the samples and the optimum concentration for maximum conductivity was found for the samples doped with 6 mol% Sm3+ at 600 °C.