对热电硫化物进行结晶学和物理性质测量
Christian Moeslund Zeuthen1, Peter Skjøtt Thorup1, Nikolaj Roth1
1Center for Materials Crystallography, Department of Chemistry and iNANO , Aarhus University , Langelandsgade 140 , Aarhus , Denmark.
Journal of the American Chemical Society
|May 3, 2019
概括
这项研究显示,硫化
科学领域:
- 材料科学
- 固态物理
- 晶体学
背景情况:
- 硫化物 (PbS) 等焦化物是重要的高性能热电材料.
- 它们的高缺陷晶体结构和运输特性缺乏基本理解.
- 观察到的特性与理想的岩盐结构一致,而不是预期的高缺陷结构.
研究的目的:
- 研究硫化物晶体结构缺陷与运输特性之间的关系.
- 澄清晶体学数据和测量的电子特性之间的差异.
- 开发一个精细的硫化结构模型.
主要方法:
- 高分辨率的同步射线粉末X射线衍射 (XRD) 用于晶体分析.
- 瑞特维尔德精细化与先进的建模,包括首选的方向和异型应变.
- 传输电子显微镜 (TEM) 用于分析结构特征和方向.
- 测量电荷载体度,电阻,移动性和西贝克系数.
主要成果:
- 在XRD的改进中,初步发现占用率极低,这与运输测量相矛盾.
- 一个新的瑞特维尔德模型将由于相关障碍导致的扩散扩散,使占用率提高到接近全量.
- TEM证实没有偏好的方向,表明扩散散是模拟布拉格强度的关键.
- 运输属性与几乎全占用相一致,而不是空位.
结论:
- 在硫化中明显的低占用率是对应性疾病的模型,而不是实际的空缺.
- 方向相关性障碍对先进材料的结构分析产生重大影响.
- 开发的建模方法可以解释先进材料的方向障碍效应.
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