原子薄的MoS2的超快电子放松动力学是由纹加速的
Ce Xu1, Guoqing Zhou2, Evgeny M Alexeev3
1School of Chemistry, Chemical Engineering and Biotechnology, and School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.
ACS nano
|August 15, 2023
概括
应变工程影响过渡金属二甲基化物 (TMD) 的超快电子放松. 纹二硫化物 (MoS2) 显示更快的放松,这表明需要长寿命热载体的应用程序的应变控制.
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
- 表面科学是一门学科.
背景情况:
- 应变工程是调整过渡金属二甲基化物 (TMD) 的光电子性能的关键.
- 之前的研究集中在纳秒载波动力学上,使得在应力下亚皮秒电子放松未被探索.
研究的目的:
- 在多层二硫化物 (ML-MoS2) 中研究应变对平秒以下电子放松动态的影响.
- 探索纹影响电子放松通路的机制.
主要方法:
- 使用时间分辨率光发射电子显微镜 (TR-PEEM) 进行实验超快速动态.
- 使用非adiabatic ab initio分子动力学 (NAMD) 进行电子放松的理论研究.
主要成果:
- 与平面ML-MoS2 (120 ± 2 fs) 相比,在纹ML-MoS2 (97 ± 2 fs) 中,在Γ谷测量了更快的电子放松.
- NAMD发现,纹增强了层运动,放松了选择规则,扰乱了结合,并增加了状态的电子密度,促进了非adiabatic合.
结论:
- 在TMD中,亚皮秒电子放松动态可以通过应变工程进行调整.
- 建议使用无纹TMD用于需要长寿命热载体的应用,例如热电子驱动光采集和光催化.
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