Effects of vacancy defects caused by non-stoichiometric ratio on dielectric properties of ABO3 perovskite (Ba0.5Sr0.5)xTiO3 ceramics |
| |
| Affiliation: | 1. Laboratoire de la Matière Condensée et des Nanosciences, Département de Physique, Faculté des Sciences de Monastir 5019, Tunisie;2. Institut Néel, CNRS et Université Joseph Fourier, BP 166, F-38042 Grenoble cedex 9, France;1. Laboratoire de la Matière Condensée et des Nanosciences, Département de Physique, Faculté des Sciences Université de Monastir, 5019, Tunisia;2. Laboratoire de Physique des Matériaux et des Nanomatériaux Appliquée à L''environnement, Faculté des Sciences de Gabes Cité Erriadh, 6079 Gabes, Tunisia;1. College of Materials Science and Engineering, State Key Laboratory of Material Processing and Die & Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, PR China;2. Information Engineering Institute, Huanghe Science and Technology College, Zhengzhou 450000, PR China;3. School of Materials Science and Engineering, The University of New South Wales, New South Wales 2052, Australia;4. Enginering Research Centre for Functional Ceramics, Ministry of Education, Huazhong University of Science and Technology, Wuhan 430074, PR China |
| |
| Abstract: | Non-stoichiometric Ba0.5Sr0.5TiO3 (BST50) ceramics with varying A/B ratios, namely (Ba + Sr)/Ti, were prepared by a conventional solid-state reaction approach. The effects of vacancy defects caused by varying the A/B ratio on the structure and dielectric properties of BST50 ceramics were systematically investigated. A remarkable change in grain size was found when the A/B ratio was increased, which led to apparent variations in the dielectric properties of the BST50 ceramics. The Curie temperature (Tc) and dielectric permittivity peak (εmax) increased first and then decreased with increasing A/B ratio, and reached the maximum at A/B = 1. Simultaneously, the dielectric diffusion parameter of BST50 ceramics was studied by the Lorenz-type formula. All samples exhibited diffusion phase transition behavior, and Tc was frequency independence. When A/B < 1, the Q value remained at a high level; in contrast, when A/B > 1, the Q value was significantly reduced. For this BST50 system, high tunability of 24.95% (at 30 kV/cm), low dielectric loss of 0.0017 (at 10 kHz), and high figure of merit (FOM) of 147 were achieved simultaneously at A/B = 1.01. |
| |
| Keywords: | Vacancy defects Non-stoichiometric ratio Dielectric properties |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
