关于 Cs2SnI2Cl2和 Cs2PbI2Cl2单层与自旋轨道合的增强热电性能的第一原则预测
Jiajia Fei1, Xiaojiao Zhang2, Jialin Li1
1Hunan Key Laboratory of Nanophotonics and Devices, School of Physics, Central South University, Changsha 410083, Hunan, People's Republic of China.
概括
全无机矿单层Cs2SnI2Cl2和Cs2PbI2Cl2由于具有高载体流动性和低导热性,显示出出色的热电潜力. 旋转轨道合显著提高了它们的优点数字 (ZT) 对于高效的能量转换.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 化烯石以其特殊的电荷传输和低导热性而闻名.
- 拉德尔斯登 - 波珀完全无机的矿具有可调节的电子和热性能.
- 热电材料有效地将热能转化为电能.
研究的目的:
- 研究Cs2SnI2Cl2和Cs2PbI2Cl2单层的电子,热和热电特性.
- 评估旋转轨道合对这些属性的影响.
- 为了确定热电应用的有前途的候选人.
主要方法:
- 使用第一原则计算来研究材料的特性.
- 旋转轨道合被纳入了电子和热电运输的计算.
- 分析了phonon-phonon相互作用以了解导热性.
主要成果:
- 两种Cs2SnI2Cl2和Cs2PbI2Cl2单层均表现出高载体流动性和低导热性.
- Cs2SnI2Cl2的热导率低于Cs2PbI2Cl2,这是由于其具有较强的声子-声子相互作用.
- 计算的功率图 (ZT) 值是有希望的,特别是当考虑旋转轨道合时,Cs2SnI2Cl2达到2.73,Cs2PbI2Cl2在700K时达到1.98.
结论:
- 在热电应用中,Cs2SnI2Cl2和Cs2PbI2Cl2单层具有有利的特性.
- 旋转轨道合显著提高了这些材料的热电性能.
- 这些全无机矿单层是下一代热电设备的有希望的候选者.
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