First-principles investigation of novel Janus Mo8S6Se6 monolayers as high-mobility semiconductors with bandgaps appropriate for low-power electronics

Abstract

Two-dimensional (2D) semiconductors characterized by environmental durability, appropriate band gaps, and impressive charge carrier mobility are essential for the advancement of next-generation optoelectronic and electronic devices. Nonetheless, the existing candidate materials encounter various challenges that impede their broader application. In this investigation, we perform an in-depth analysis of the stability, elasticity, and optoelectronic properties, along with carrier mobility, of the proposed Janus P3m1, Cmm2, and C2/m-Mo₈S₆Se₆ monolayers. Our findings reveal that all the structures under consideration demonstrate exceptional thermodynamic and mechanical stability. Furthermore, the calculated band gaps for the P3m1, Cmm2, and C2/m-Mo₈S₆Se₆ monolayers are 1.49 eV, 1.44 eV, and 1.42 eV, respectively. These monolayer structures also exhibit outstanding ductility and light absorption coefficients of 10⁵ cm⁻¹ spanning the near-infrared to visible light spectrum. Importantly, these monolayers exhibit significant anisotropic carrier mobility, recorded at 10⁴ cm² V⁻¹ s⁻¹. Overall, these innovative Mo₈S₆Se₆ monolayers contribute to the diversity of 2D optoelectronic materials, providing promising options for future electronic and optoelectronic devices.