First-principles investigations of structural and electronic properties of SnAs/SnAsCl heterostructure

In this work, we investigate the tunable structural and electronic properties of SnAs monolayer through chlorinated functionalization and the SnAs/SnAsCl heterostructure construction. Through chlorinated functionalization, we observe a remarkable transformation of the SnAs monolayer into a semiconducting SnAsCl monolayer with a direct band gap of 1.32 eV. This demonstrates the potential for controlling and tuning the electronic properties of SnAs through surface functionalization. Moreover, depending on the specific stacking patterns in the SnAs/SnAsCl heterostructure, we observe the formation of either Ohmic contact or Schottky contact. Particularly noteworthy is the presence of ultra-low Schottky barriers, measured at 0.03 eV, charge transport efficiency and improving device performance. The SnAs/SnAsCl heterostructure exhibits small tunneling probability, indicating a relatively low electron transparency. These findings pave the way for the development of high-performance electronic devices utilizing these heterostructures and offer promising opportunities for future technological advancements. © 2023 Elsevier B.V.