Bandgap Transition of 2H Transition Metal Dichalcogenides: Predictive Tuning via Inherent Interface Coupling and Strain
Bandgap Transition of 2H Transition Metal Dichalcogenides: Predictive Tuning via Inherent Interface Coupling and Strain
复制标题
DOI：
10.1021/acs.jpcc.5b12677
复制
发表时间：
2016-04
影响因子：
3.7
通讯作者：
B. Ouyang;Z. Mi;Jun Song
中科院分区：
文献类型：
--
作者：
B. Ouyang;Z. Mi;Jun Song
二维过渡金属二硫属化物（TMD）内的相变为设计其性能提供了新的可能性。利用第一性原理密度泛函理论（DFT）计算，我们系统地研究了几种IV族TMD中2H相单层与其多晶相之间的界面电子耦合，MoS2（MoSe2）和WS2（WSe2），固有的双层异质结构。结果发现，界面耦合，增强面内应变，可以大大修改的能带结构的2H相诱导带隙转变（间接到直接或直接到间接）。此外，应变对能带结构的影响可以很好地理解和预测的框架内的变形势理论。本研究提供了重要的见解工程的TMD为基础的设备的光电性能。
Phase transitions within two-dimensional transition metal dichalcogenides (TMD) promise new possibilities for engineering their properties. Using first-principles density functional theory (DFT) calculations, we systematically examined the interfacial electronic coupling between the 2H phase monolayer with its polymorphic phases in several group IV TMD, i.e., MoS2 (MoSe2) and WS2 (WSe2), inherent bilayer heterostructures. It is found that the interface coupling, augmented by in-plane strain, can greatly modify the band structure of the 2H phase to induce bandgap transition (either indirect-to-direct or direct-to-indirect). Moreover, the effects of strain on the band structure can be well understood and predicted within the framework of deformation potential theory. The present study provides important insights toward engineering optoelectronic properties of TMD-based devices.