在无形La-Fe-Sb混合物中抑制二进制核化
Joshua R Williams1, Mark B Johnson, David C Johnson
1Department of Chemistry and Materials Science Institute, University of Oregon, Eugene, Oregon 97403, USA.
Journal of the American Chemical Society
|March 20, 2003
概括
添加兰抑制了La{x}Fe{y}Sb{z}反应物中的二相核化,扩大了三元 skutterudite La{x}Fe{4}Sb{12}形成的组成范围. 这会影响核化能量和化合物合成.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 斯库特鲁迪特化合物,如La{x}Fe{4}Sb{12}等,对热电应用具有兴趣.
- 控制这些复杂材料的核和生长对于优化它们的性能至关重要.
- 反应物组成对核化途径的影响尚未完全理解.
研究的目的:
- 为了研究La{x}Fe{y}Sb{z}调制的元素反应物的核化能量.
- 确定Fe/Sb比对三元 skutterudite化合物La{0.5}Fe{4}Sb{12}核化的影响.
- 了解在抑制二进制相核形成中的作用.
主要方法:
- 在Fe/Sb比率的范围内测量La{x}Fe{y}Sb{z}反应物的核化能量.
- 在三元La-Fe-Sb系统与二元Fe-Sb系统中核化行为的比较.
- 分析了添加对FeSb核化的影响.
主要成果:
- 拉0.5Fe4Sb12的核能强烈取决于Fe/Sb的比率,随着它偏离1:3的刻度值而增加.
- 在调制反应剂中,添加兰抑制了FeSb(2) 的核化.
- 对于三元 skutterudite 核化的 Fe/Sb 组成范围因的存在而扩大.
结论:
- 铁/Sb比率是控制核化能量和形成La(x) Fe(4) Sb(12) skutterudites的关键因素.
- 兰可以抑制二元FeSb的核化,从而促进三元化合物的形成.
- 这些发现与理论预测一致,并解释了从无形中间体中转移稳定相的核形成.
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