Tunable photoelectric properties of monolayer Mo 1- x W x Te 2 alloys: a first-principles study

• Published in: RSC advances 2024-09, Vol.14 (42), p.31117-31125
• Main Authors: Gao, Mohan, Wang, Zhenhua, Ma, Jinchao, Jiang, Haowen, Fu, Yuanyuan, Huo, Suifeng, Zhang, Hui, Wu, Chen, Chai, Kan, Ji, Guangju
• Format: Article
• Language: English
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/d4ra04653f

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, Mo W Te 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.