Thickness dependence of hydrogen-induced phase transition in MoTe2
Thickness dependence of hydrogen-induced phase transition in MoTe2
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DOI：
10.1103/physrevb.101.144104
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发表时间：
2020-04-21
影响因子：
3.7
通讯作者：
Dev, Pratibha
中科院分区：
文献类型：
--
作者：
Manchanda, Priyanka;Kumar, Pankaj;Dev, Pratibha
二维（2D）过渡金属二硫属化物（TMD）通常存在于具有不同物理性质的两个或更多个结构相中，并且可以通过不同的刺激在这些相之间重复切换，使得它们潜在地用于存储器件。了解TMD与传统半导体或形成异质或同质组件的其他2D晶体之间的界面物理特性，是其在技术中成功应用的关键。然而，迄今为止，大多数的理论工作都是探讨孤立的TMD单分子膜在真空中的相变特性。使用从头计算，我们展示了界面效应如何修改相变的热力学和动力学通过研究氢诱导的MoTe2单层和双层的转变。MoTe2的相变特性显示出很大的厚度依赖性，在氢化双层中的过渡的时间尺度是在室温下单层中的约107倍长。我们的研究强调了在预测二维晶体的性质时考虑直接环境影响的重要性。
Two-dimensional (2D) transition metal dichalcogenides (TMDs) usually exist in two or more structural phases with different physical properties, and can be repeatedly switched between these phases via different stimuli, making them potentially useful for memory devices. An understanding of the physics of interfaces between the TMDs and conventional semiconductors, or other 2D crystals forming heterogenous or homogeneous assemblies, is central to their successful application in technologies. However, to date, most theoretical works have explored phase-change properties of isolated TMD monolayers in vacuum. Using ab initio calculations, we show how interfacial effects modify the thermodynamics and kinetics of the phase transition by studying hydrogen-induced transitions in monolayers and bilayers of MoTe2. The phase-change properties of MoTe2 show substantial thickness dependence, with the timescale for a transition in the hydrogenated bilayer being about 107 times longer than that in a monolayer at room temperature. Our study highlights the importance of taking effects of immediate environment into account when predicting properties of 2D crystals.