Electronic and optical properties of fully fluorinated Janus MoSSe monolayer

The electronic and optical property variations of fully fluorinated Janus MoSSe were investigated based on first-principles calculations. After the fluorination process, the band gaps of Janus MoSSe, F₁₆–SeMoS, F₁₆–SMoSe, and F₁₆–SeMoS–F₁₆ were 1.46, 1.07, 0.31, and 0.24 eV, respectively. At the same time, the work functions of Janus MoSSe, F₁₆–SeMoS, F₁₆–SMoSe, and F₁₆–SeMoS–F₁₆ were 5.20, 5.74, 4.52, and 6.15 eV, respectively. Furthermore, these optical properties can be effectively modulated by fluorination; in particular, F₁₆–SMoSe demonstrated the best visible light response property, resulting in more promising potential in photocatalytic and photovoltaic applications. Therefore, through the facile fluorination process, the relevant properties of Janus MoSSe can be adjusted effectively, which can largely expand the applications of Janus MoSSe in electronic/optoelectronic devices and photocatalysts.