超低的晶格导热率在I型迪拉克MBene TiB2中
Ashish Sharma1, Vir Singh Rangra1
1Department of Physics, Himachal Pradesh University, Summer Hill, Shimla, Himachal Pradesh 171005, India.
概括
我们研究了二化物 (TiB2) MBenes,发现层数大大改变了电子和传输特性. 单层TiB2 MBenes显示出有前途的热电性能,与双层不同.
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
- 计算材料科学科学 计算材料科学
背景情况:
- 一个新的2D过渡金属化物类别MBenes正在引起人们的注意.
- 这些二维材料的运输研究很少,但对于理解它们的特性至关重要.
研究的目的:
- 为了研究TiB2 MBenes系统的依赖层的电子和传输特性.
- 探索层数对电子结构,热导率和热电性能的影响.
主要方法:
- 使用博尔茨曼运输理论与ab-initio密度函数理论计算相结合.
- 检查电子带结构,包括迪拉克特征.
- 计算异质的室温和高温网格导热率.
- 评估电子运输系数和热电功率 (ZT).
主要成果:
- 单层 (ML) TiB2 MBenes表现出迪拉克半金属特征,而双层 (BL) 由于改变的迪拉克圆,显示了II型韦尔金属行为.
- 观察到异型晶格导热率,高温时的超低值归因于声子散射和迪拉克状态.
- 单层TiB2 MBenes显示出一个有希望的室温热电功率 (ZT) 值为1.71,明显高于双层的0.38.
结论:
- 层次的数量极大地影响了TiB2 MBenes的电子和传输特性.
- TiB2 MBenes具有超低的导热率,使其适用于热电应用.
- 单层TiB2 MBenes在室温热电能转换方面具有很好的潜力.
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