Tuning the electronic structure of {\alpha}-antimonene monolayer through interface engineering

TL;DR

This paper demonstrates how interface engineering can modify the electronic properties of { extalpha}-antimonene monolayers, enabling control over their semiconducting or semimetallic behavior for potential technological applications.

Contribution

It shows that interface engineering can effectively tune the electronic structure of epitaxial { extalpha}-antimonene monolayers, achieving a nearly freestanding semiconductor with a tunable band gap.

Findings

Successfully obtained a nearly freestanding semiconducting { extalpha}-antimonene monolayer with a ~170 meV band gap.

Observed a semiconductor-semimetal crossover in bilayer { extalpha}-antimonene.

Demonstrated interface engineering as a viable method to modify 2D vdW material properties.

Abstract

The interfacial charge transfer from the substrate may influence the electronic structure of the epitaxial van der Waals (vdW) monolayers and thus their further technological applications. For instance, the freestanding Sb monolayer in puckered honeycomb phase ({\alpha}-antimonene), the structural analog of black phosphorene, was predicted to be a semiconductor, but the epitaxial one behaves as a gapless semimetal when grown on the Td-WTe2 substrate. Here, we demonstrate that interface engineering can be applied to tune the interfacial charge transfer and thus the electron band of epitaxial monolayer. As a result, the nearly freestanding (semiconducting) {\alpha}-antimonene monolayer with a band gap of ~170 meV was successfully obtained on the SnSe substrate. Furthermore, a semiconductor-semimetal crossover is observed in the bilayer {\alpha}-antimonene. This study paves the way towards modifying the electron structure in two-dimensional vdW materials through interface engineering.