Gao Mohan, Wang Zhenhua, Ma Jinchao, Jiang Haowen, Fu Yuanyuan, Huo Suifeng, Zhang Hui, Wu Chen, Chai Kan, Ji Guangju
Department of Physics, School of Science, Harbin University of Science and Technology Harbin 150080 P.R. China
RSC Adv. 2024 Sep 30;14(42):31117-31125. doi: 10.1039/d4ra04653f. eCollection 2024 Sep 24.
Monolayer MoTe and WTe within the two-dimensional transition metal dichalcogenides (TMDCs) material family exhibit broad potential for application in optoelectronic devices owing to their direct band gap characteristics. In this work, upon alloying these materials into a monolayer system denoted as Mo W Te, intriguing alterations are observed in the electronic and optoelectronic properties. The photoelectric attributes of these alloys can be tailored by manipulating the respective ratios of molybdenum to tungsten (Mo/W). This investigation employs first-principles calculations based on density functional theory (DFT) to assess physical traits of two-dimensional monolayered structures composed from varying compositions of Mo W Te. Our findings reveal that while maintaining a direct band gap characteristic across all compositions studied, there is also a reduction observed in electron effective mass near the Fermi level. Moreover, changing in the Mo/W ratio allows gradual adjustments in electronic properties such as density of states (DOS), work function, dielectric function, absorptivity, and reflectivity. Phonon dispersion curves further demonstrate the stability of Mo W Te systems. Notably, MoWTe exhibits lower polarizability and reduced band gap when compared against MoTe and WTe counterparts. This research underscores how alloying processes enable customizable modifications in the electronic and optoelectronic properties of Mo W Te monolayer materials which is essential for enhancing nanoscale electronic and optoelectronic device design.
二维过渡金属二硫属化物(TMDCs)材料家族中的单层MoTe和WTe,由于其直接带隙特性,在光电器件中具有广泛的应用潜力。在这项工作中,将这些材料合金化形成一种称为MoWTe的单层体系时,其电子和光电特性出现了有趣的变化。这些合金的光电属性可以通过控制钼与钨(Mo/W)的各自比例来进行调整。本研究采用基于密度泛函理论(DFT)的第一性原理计算,来评估由不同组成的MoWTe构成的二维单层结构的物理特性。我们的研究结果表明,在所研究的所有组成中,虽然都保持直接带隙特性,但在费米能级附近电子有效质量也有所降低。此外,改变Mo/W比例可以逐渐调整诸如态密度(DOS)、功函数、介电函数、吸收率和反射率等电子特性。声子色散曲线进一步证明了MoWTe体系的稳定性。值得注意的是,与MoTe和WTe相比,MoWTe表现出更低的极化率和减小的带隙。这项研究强调了合金化过程如何能够对MoWTe单层材料的电子和光电特性进行可定制的修改,这对于增强纳米级电子和光电器件设计至关重要。