High Anisotropic Optoelectronics in Monolayer Binary M8X12 (M = Mo, W; X = S, Se, Te)

Yi Peng; Qianqian Zhu; Wangping Xu; Juexian Cao

doi:10.1021/acsami.2c05169

High Anisotropic Optoelectronics in Monolayer Binary M₈X₁₂ (M = Mo, W; X = S, Se, Te)

ACS Appl Mater Interfaces. 2022 Jun 6. doi: 10.1021/acsami.2c05169. Online ahead of print.

Authors

Yi Peng¹, Qianqian Zhu¹, Wangping Xu², Juexian Cao²

Affiliations

¹ School of Physics and Electronic-Electrical Engineering, Xiangnan University, Chenzhou 423000, P. R. China.
² Department of Physics & Hunan Institute of Advanced Sensing and Information Technology, Xiangtan University, Xiangtan 411105, P. R. China.

PMID: 35666942
DOI: 10.1021/acsami.2c05169

Abstract

Exploring high performance and excellent ambient stability in two-dimensional (2D) monolayer photoelectric materials is motivated by not only practical applications but also scientific interest. Here, a new 2D monolayer W₈Se₁₂ structure is synthesized via in situ electron-beam irradiation on 2D WSe₂. Moreover, we systematically studied the photoelectric properties of the class of monolayer M₈X₁₂ (M = Mo, W; X = S, Se, and Te) materials by first principles. The results indicated that Mo₈S₁₂, Mo₈Se₁₂, W₈S₁₂, and W₈Se₁₂ monolayers possess desirable direct band gaps and remarkable anisotropic optical absorption in visible light, while Mo₈Te₁₂ and W₈Te₁₂ monolayers are metals. Impressively, the monolayer W₈Se₁₂ can result in a direct-indirect-metal transition under uniaxial strain. In addition, they show high anisotropic carrier mobilities (up to 10⁴ cm² V^-1 s^-1), significantly over those of transition-metal dichalcogenides. These new binary monolayer M₈X₁₂ structures can effectively broaden the 2D material family and may provide four potential candidates in photoelectric applications.

Keywords: direct band gaps; high mobility; in situ electron-beam irradiation; photoelectric properties; two-dimensional.