Investigating electronic structure and optical property variations in full and semi-hydrogenated Janus MoSSe monolayers

Abstract

By employing first principles calculations, we have developed three novel and stable hydrogenated Janus MoSSe materials, and conducted a comparative investigation of their electronic structures and optical properties. The pristine Janus MoSSe demonstrates characteristics of a direct band gap semiconductor with a band gap of 1.60 eV, exhibiting properties typical of a P-type semiconductor. Upon complete hydrogenation on the S side and Se side, the band gap decreases to 0.84, 0.34, resulting in N-type, P-type semiconductors, respectively. while the hydrogenation on both sides, the band gap is 0, and the material show metallic property. The work functions after hydrogenation are consistently lower than those of the pristine Janus MoSSe. In terms of optical properties, the absorption intensity in the visible light range is higher for the S side case than the Se side case, while the reflectivity of the S side case is lower. This indicates that the S side case is more suitable for applications in photo-electric devices in both the visible light and infrared ranges. Therefore, through first principles calculations, we have explored three types of novel and stable hydrogenated Janus MoSSe configurations, examining their fundamental properties and potential applications.