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通过强大的粘接相互作用,增强2H-CrX₂ (X = S和Se) 单层中的声子热传输

Shuwei Tang^1,2, Da Wan¹, Shulin Bai¹

¹College of Materials Science and Engineering, Liaoning Technical University, Zhonghua Road. #47, Fuxin, Liaoning, 123000, China. tangsw911@nenu.edu.cn.

Physical chemistry chemical physics : PCCP

|August 15, 2023

概括

该研究探讨了2H-CrX2 (X = S, Se) 单层,发现它们是具有高热导率的稳定直接半导体. 声波边界散射显著影响它们的热传输特性.

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:

发现2H-MoS2单层突出了二维材料的潜力.
了解相关过渡金属二甲基化物的特性对于新型应用至关重要.
2H-CrX2 (X = S, Se) 单层是先进材料的有希望的候选材料.

研究的目的:

从理论上评估2H-CrX2 (X = S, Se) 单层的电子结构,结构稳定性和热传输.
调查导致它们导热性的因素.
为2H相热管理材料的实验研究提供理论指导方针.

主要方法:

密度函数理论 (DFT) 对电子结构和稳定性的计算.
半经验博尔兹曼运输理论用于热传输分析.
在初始分子动力学 (AIMD) 模拟中进行热稳定性评估.

主要成果:

2H-CrX2 (X = S, Se) 单层是带间隙分别为0.91和0.69 eV的直接半导体.
通过弹性常数,声子分散和AIMD模拟证实了出色的机械,动态和热稳定性.
高热导率为131.7 W m-1 K-1 (2H-CrS2) 和88.6 W m-1 K-1 (2H-CrSe2) 在300 K时被计算出来.
识别出phonon边界散射是影响格子导热性的主要因素.

结论:

2H-CrX2 (X = S, Se) 单层表现出有前途的电子和热性能.
它们的稳定性和高导热性使它们适合用于热管理应用.
这些发现为实验研究提供了基本的见解和理论指导.

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