伊特和元素的共和形成双矿结构Ba的形成
Runyu Mao1, Deyi Zheng1, Qiyun Wu1
1College of Materials and Metallurgy, Guizhou University, Guiyang 550025, China.
Materials (Basel, Switzerland)
|June 10, 2023
概括
和添加的无压陶由于形成新的双矿相和R-O-T相共存而表现出增强的压电特性. 这使得它们成为以为基础的材料的有希望的替代品.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 陶工程 陶工程 陶工程
背景情况:
- 无压陶在环境和健康方面至关重要.
- 基于酸,酸和酸 (BCZT) 的材料正在作为无替代品进行探索.
- 使用兴奋剂策略来增强BCZT陶的压电特性.
研究的目的:
- 调查与 (Y3+) 和 (Nb5+) 联合兴奋剂对无 (Ba0.85Ca0.15) ((Ti0.90Zr0.10) O3 (BCZT) 压陶的作用.
- 了解协同兴奋剂对缺陷化学,相结构,微观结构和电气性能的影响.
- 为了确定最佳的兴奋剂度,以提高压电性能.
主要方法:
- 传统的固态烧结方法用于样品制备.
- 用于相位分析和瑞特维尔德精炼的X射线衍射 (XRD).
- 传输电子显微镜 (TEM) 用于微结构和相位分析.
- 用X射线光电子光谱 (XPS) 进行缺陷化学分析.
- 电气性能测量包括压电常数 (d33),平面电机合系数 (kp),介电常数 (εr) 和库里温度 (TC).
主要成果:
- 与伊和联合剂显著增强了压电特性.
- 观察到一个新的双矿阶段的形成,即二氧化物 (Ba2YNbO6).
- R-O-T阶段的并存得到了XRD Rietveld提炼和TEM的证实.
- 在x = 0.1 mol%的兴奋剂下达到最佳性能,d33 = 667 pC/N和 kp = 0.58.
- 随着兴奋剂的使用,观察到里温度 (TC = 92 °C) 略微升高.
结论:
- 和的联合剂有效地改善了BCZT陶的压电特性.
- Ba2YNbO6阶段的形成和R-O-T阶段的共存是提高性能的关键因素.
- 优化的BCZT-x(Nb + Y) 组成为传统的以为基础的压电材料提供了一个可行的无替代品.
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