Colossal Permittivity Characteristics and Origin of (Sr, Sb) Co-Doped TiO2 Ceramics

Abstract

With the continuous development of electronic technology, the application of dielectric materials is also becoming more and more abstractive. It is also a great challenge to find a new type of colossal permittivity material with high dielectric permittivity, lower dielectric loss and excellent temperature and frequency stability. In this work, the (Sr1/3Sb2/3) x Ti1−x O2 (SSTO) colossal permittivity ceramics for x = 0, 0.5%, 1.0%, 1.5%, 2.0%, 4.0% were prepared by conventional solid state reaction method. The crystal structure, microstructure, dielectric properties, varistor properties were analyzed, and the formation mechanism of colossal dielectric was revealed. When the doping amount is 2%, SSTO has the optimal dielectric performance with dielectric constant of approximately 2.2 × 104, dielectric loss of about 0.03 at 1 kHz. X-ray photoelectron spectroscopy (XPS) and Impedance spectra (IS) results showed that defect clusters and interface polarization are the main reasons for the improvement of dielectric properties of (Sr, Sb) co-doped TiO2 ceramics. Therefore, this work is of great significance for the development and application of TiO2-based new colossal dielectric materials.