A family of flexible two-dimensional semiconductors: MgMX 2 Y 6 (M = Ti/Zr/Hf; X = Si/Ge; Y = S/Se/Te)

• Published in: Journal of semiconductors 2023-04, Vol.44 (4), p.42101
• Main Authors: Yuan, Junhui, Xue, Kanhao, Miao, Xiangshui, Ye, Lei
• Format: Article
• Language: English
• ISSN: 1674-4926; 2058-6140
• DOI: 10.1088/1674-4926/44/4/042101

Inspired by the recently predicted 2D MX 2 Y 6 (M = metal element; X = Si/Ge/Sn; Y = S/Se/Te), we explore the possible applications of alkaline earth metal (using magnesium as example) in this family based on the idea of element replacement and valence electron balance. Herein, we report a new family of 2D quaternary compounds, namely MgMX 2 Y 6 (M = Ti/Zr/Hf; X = Si/Ge; Y = S/Se/Te) monolayers, with superior kinetic, thermodynamic and mechanical stability. In addition, our results indicate that MgMX 2 Y 6 monolayers are all indirect band gap semiconductors with band gap values ranging from 0.870 to 2.500 eV. Moreover, the band edges and optical properties of 2D MgMX 2 Y 6 are suitable for constructing multifunctional optoelectronic devices. Furthermore, for comparison, the mechanical, electronic and optical properties of In 2 X 2 Y 6 monolayers have been discussed in detail. The success of introducing Mg into the 2D MX 2 Y 6 family indicates that more potential materials, such as Ca- and Sr-based 2D MX 2 Y 6 monolayers, may be discovered in the future. Therefore, this work not only broadens the existing family of 2D semiconductors, but it also provides beneficial results for the future.