在施加外部应变下,双层和异层IV组单基因体的堆叠依赖于压电反应
Kevin Tran1, Michelle J S Spencer1
1School of Science, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia. michelle.spencer@rmit.edu.au.
Nanoscale
|March 5, 2025
概括
第四组单基二层表现出增强的压电特性,特别是SnSe和GeSe/SnSe异质二层. 施加的应变显著提高了压电反应,使这些材料成为纳米级压电和光电子设备的理想选择.
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:
- 多层的二维 (2D) 材料为先进的设备提供了独特的特性.
- 第四组单基化物 (MX,M = Ge/Sn,X = S/Se) 在单层形式表现出强大的压电性和光学吸附性.
- 这些材料的双氧化和异氧化配置可能会产生新的特性.
研究的目的:
- 研究IV组单基二层和异二层的堆叠依赖的压电反应.
- 探索施加的应变对它们的压电和电子性能的影响.
- 评估它们在压电和光电子设备应用中的潜力.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 分析了IV组单基二层和异二层的堆叠配置.
- 计算的压电系数 (例如,e22) 带有和没有施加的应变.
主要成果:
- 在单层 (0.86 C m−2) 和双层 (1.36 C m−2) 形式中,SnSe表现出最高的压电反应.
- GeSe/SnSe异构体表现出最大的压电系数 (1.58 C m−2).
- 施加的应变极大地提高了双层SnSe的压电反应,达到6.13 C m-2,增加了约450%,显著超过了其他分层材料.
- GeSe/SnSe异构体显示了II型带间隙,表明了光电子应用的潜力.
结论:
- 第四组单基二层在应力下具有非凡的压电反应的潜力.
- 这些材料是下一代基于纳米的压电和光电子设备的有希望的候选者.
- 应变工程提供了一条可行的途径,可以显著提高它们的性能.
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