高性能热电材料的高通量选使用吉布斯自由能量和电子负性
Guiying Xu1, Jiakai Xin1, Hao Deng1
1Beijing Municipal Key Lab. of Advanced Energy Materials and Technology, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Materials (Basel, Switzerland)
|August 12, 2023
概括
一种新的高通量选方法使用摩拉吉布斯自由能量和电子负性来识别有前途的热电材料. 这种方法避免了实验和复杂的计算,加速了有效的能量转换材料的发现.
科学领域:
- 材料科学 材料科学 材料科学
- 能源转换 能源转换
- 固态物理 固态物理
背景情况:
- 热电 (TE) 材料可以直接将热能转化为电能,这对于能源采集和废热回收至关重要.
- 识别高性能TE材料并提高其性能是能源材料领域的关键研究目标.
- 目前的选方法通常依赖于广泛的实验或计算密集的第一原则计算.
研究的目的:
- 提出一种新的,高通量选方法,用于识别潜在的热电材料.
- 建立基于材料性能的客观标准,以预测热电性能.
- 通过选已知和新型候选材料来验证拟议的方法.
主要方法:
- 开发了一种选方法,该方法基于摩尔基布斯自由能量 (Gm) 与电子负性 (X) 和 TE 特性之间的关系.
- 对一系列典型和非典型的热电材料计算了Gm和X.
- 利用现有的热化学数据和元素电子负性值,消除了对实验或ab initio计算的需求.
主要成果:
- 确立了Gm (-130.20至-248.82 kJ/mol) 和X (1.80至2.21) 的特定范围,作为高性能TE材料的有效选标准.
- 对15种典型的和9种广泛研究的TE材料成功验证了标准,Mg2Si是一个小例外.
- 从102种非典型化合物中确定了64种潜在的TE材料,从热化学数据中确定了44种纯物质,其中包括几个碳化物.
结论:
- 采用Gm和X的拟议方法,提供了一种快速且具有成本效益的方法来选高性能热电材料.
- 确定的标准 (Gm = -130.20~-248.82 kJ/mol和X = 1.80~2.21) 是 TE潜力的可靠预测指标.
- 这种方法通过利用易于获得的数据,显著加快了新型 TE 材料的发现,包括有前途的碳化物.
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