在单层1T-ZrS2和ZrS2/ZrSe2异质连接的热性质中引起的应变
Yanshen Zhao1, Lu Yang2, Huaidong Liu1
1School of Architecture and Civil Engineering, Shenyang University of Technology, Shenyang, 110870, China.
Journal of molecular modeling
|March 6, 2024
概括
应变工程显著改变了ZrS2,ZrSe2的热特性及其异构结构. 应用双轴拉伸应变调整热参数,并可能导致异极连接处的声子撕裂,影响材料稳定性.
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:
- 在不同的应变条件下研究单层ZrS2,ZrSe2及其异构结构.
- 使用第一原则计算分析声子散射曲线和热性质.
研究的目的:
- 系统地分析双轴拉伸应变对ZrS2,ZrSe2单层和ZrS2/ZrSe2异构结构的声子光谱和热性质的影响.
- 确定这些材料的应变极限,并了解像声撕裂这样的潜在失效机制.
主要方法:
- 使用密度函数理论 (DFT) 与PBE通用梯度近似 (GGA) 交换相关函数.
- 运用密度函数扰动理论 (DFPT) 来计算声子光谱和完整的动态矩阵.
- 优化结构使用非保守的伪潜力方法,并指定了收标准.
主要成果:
- 单层ZrS2和ZrSe2可以承受高达8%的双轴拉伸应变;ZrS2/ZrSe2异质连接可以承受高达6%的拉伸应变.
- 异质连接中的范德瓦尔斯力可以诱导垂直声撕裂.
- 双轴拉伸应变有效调整热特性 (,,自由能量,热容量) 随着温度的增加.
结论:
- 应变工程是一种可行的方法来修改ZrS2,ZrSe2及其异构结构的热特性.
- 材料在应变极限时,其热性能和潜在不稳定性 (虚构频率) 呈现出显著的变化.
- 了解应变效应对于设计用于热管理应用的先进二维材料至关重要.
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