Band Gap Engineering of MoxW1-xS2 Alloy Monolayers with Wafer-Scale Uniformity

• Published in: Inorganic chemistry 2024-04, Vol.63 (17), p.7714-7724
• Main Authors: Zhou, Zhonghao, Zhang, Xingchen, Chen, Xinya, Cheng, Zhihai, Wang, Zhiyong
• Format: Article
• Language: English
• ISSN: 1520-510X
• DOI: 10.1021/acs.inorgchem.3c04644

Modulating the band gap of two-dimensional (2D) transition metal dichalcogenide (TMDC) semiconductors is critical for their application in a wider spectral range. Alloying has been demonstrated as an effective method for regulating the band gap of 2D TMDC semiconductors. The fabrication of large-area 2D TMDC alloy films with centimeter-scale uniformity is fundamental to the application of integrated devices. Herein, we report a liquid-phase precursor one-step chemical vapor deposition (CVD) method for fabricating a MoxW1-xS2 alloy monolayer with a large size and an adjustable band gap. Good crystalline quality and high uniformity on a wafer scale enable the continuous adjustment of its band gap in the range of 1.8-2.0 eV. Density functional theory calculations provided a deep understanding of the Raman-active vibration modes of the MoxW1-xS2 alloy monolayer and the change in the conductivity of the alloy with photon energy. The synthesis of large-area MoxW1-xS2 alloy monolayers is a critical step toward the application of 2D layered semiconductors in practical optoelectronic devices.