SnO2掺杂Ba0.6Sr0.4TiO3陶瓷的改性机理与介电性能调控研究
Modification Mechanism and Dielectric Property Regulation of SnO2-Doped Ba0.6Sr0.4TiO3 Ceramics
张涛 1孙兰兰 2王梅 2刘佳 3李敏 2冯家乐3
作者信息
- 1. 西安科技大学 材料科学与工程学院,陕西 西安 710054;西安科技大学 理学院,陕西 西安 710054
- 2. 西安科技大学 理学院,陕西 西安 710054
- 3. 西安科技大学 材料科学与工程学院,陕西 西安 710054
- 折叠
摘要
钛酸锶钡(BarSr1-rTiO3,BST)铁电材料具有良好的介电、铁电、热释电性能,因而成为动态随机存储器、微波调谐器及移相器等应用中的重要材料之一.采用固相烧结法制备(1-r)Ba0.6Sr0.4TiO3-rSnO2(BST-Sn)陶瓷,通过X线衍射、扫描电镜及LCR数字电桥测试系统,并结合第一性原理理论计算研究不同SnO2 掺杂量对BST体系微观结构和介电性能的影响.结果表明,随着SnO2 掺杂量的增加,BST晶格常数c与a的比(晶轴比c/a)减少,材料禁带宽度增大.当SnO2 掺杂量(摩尔比)为0.05时,其带隙达到最大值(1.889 eV).能带与态密度结果表明,其带隙增大是由Ti原子的3d轨道向高能方向移动所致,实验制备出纯BST陶瓷的介电常数为3 227,SnO2 的引入降低了BST陶瓷的介电常数.
Abstract
Barium strontium titanate(BarSr1-rTiO3,BST)ferroelectric material is considered an important ma-terial in dynamic random access memory,microwave tuner,phase shifter,and other applications because of its good dielectric,ferroelectric,and pyroelectric properties.In this study,the(1-r)Ba0.6Sr0.4TiO3-rSnO2(BST-Sn)ce-ramics were prepared via the solid-phase sintering method.The effects of different contents of SnO2 on the micro-structure and dielectric properties of the BST system were examined via X-ray diffraction,scanning electron micros-copy,and the LCR digital bridge test system.The theoretical calculation results show that the ratio of lattice con-stant c to lattice constant a of BST decreases and the band gap increases with an increase in the incorporation ratio of SnO2.When the doping ratio of SnO2 is 0.05,the band gap reaches a maximum of 1.889 eV.The results of band and state density show that an increase in band gap is caused by the movement of Ti atoms'3d orbitals towards high energy.Secondly,the dielectric constant of pure BST ceramics,prepared experimentally,is 3 227,and the intro-duction of SnO2 reduces the dielectric constant of BST ceramics.
关键词
第一性原理/SnO2掺杂BST/BST陶瓷/电子结构/固相烧结法Key words
first principles/SnO2 doped BST/BST ceramic/electronic structure/solid state sintering method引用本文复制引用
基金项目
国家自然科学基金资助项目(52174151)
国家自然科学基金资助项目(11974275)
陕西省联合基金重点资助项目(2021JML-05)
出版年
2024
NETL
NSTL
万方数据