化二维钻石的取决于层的热和热电性能
Samir El Masaoudi1, Pascal Puech2, Fabrice Piazza3
1Laboratoire de Physico-Chimie des Nano-objets (LPCNO), UMR5215 CNRS, INSA, 135 avenue de Rangueil, Toulouse 31077, France.
概括
化少层石墨烯,或钻石,显示可调节的热和热电性能. 比拉耶尔钻石 (2LD) 具有出色的热电性能,使这些材料在能源应用中具有前景.
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
- 纳米技术 纳米技术
背景情况:
- 含的几层石墨烯,包括石墨烯和钻石 (2LD,3LD),是具有可调节电子特性的新2D纳米材料.
- 了解它们的热和热电行为对于先进的应用至关重要.
研究的目的:
- 理论上研究化石墨烯基材料的热和热电特性:石墨烯,双层二 (2LD) 和三层二 (3LD).
- 评估化和层间粘合对导热率和热电效率的影响.
主要方法:
- 声波散射关系是使用和近似 (HA) 计算的,用于动态稳定性.
- 准-HA用于体积依赖的数量和热膨胀.
- 博尔兹曼运输方程解决了格子导热率.
- 用恒定放松时间近似计算评估的热电特性.
主要成果:
- 钻石结构呈现正热膨胀,而石墨烯在低温下呈现负膨胀.
- 格子的导热率在300 K:石墨烯 (574 W·m−1·K−1),2LD (1314 W·m−1·K−1),3LD (1282 W·m−1·K−1). 它们的导热率是:
- 化显著提高了西贝克系数; 2LD显示了最高的优点数字 (ZT ≈ 1.2 × 10−2在300 K).
结论:
- 化石墨烯结构提供可调节的热传输和热电效率.
- 比利亚尔钻石 (2LD) 显示出优越的热电性能.
- 这些材料具有纳米级热管理和能量转换设备的巨大潜力.
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