Few-layer antimonene electrical properties

TL;DR

This study provides the first experimental characterization of the electrical properties of few-layer antimonene, revealing stable conductivity and mobility in ambient conditions, supported by theoretical insights into topologically protected surface states.

Contribution

It offers the first experimental measurements of electrical properties of few-layer antimonene and links these findings to topologically protected surface states through theoretical calculations.

Findings

Sheet resistance of ~1200 Ω/sq measured in ambient conditions

Mobility of ~150 cm²V⁻¹s⁻¹ observed, independent of flake thickness

Theoretical evidence suggests topologically protected surface states influence electronic properties

Abstract

Antimonene -- a single layer of antimony atoms -- and its few layer forms are among the latest additions to the 2D mono-elemental materials family. Numerous predictions and experimental evidence of its remarkable properties including (opto)electronic, energetic or biomedical, among others, together with its robustness under ambient conditions, have attracted the attention of the scientific community. However, experimental evidence of its electrical properties is still lacking. Here, we characterized the electronic properties of mechanically exfoliated flakes of few-layer (FL) antimonene of different thicknesses (~ 2-40 nm) through photoemission electron microscopy, kelvin probe force microscopy and transport measurements, which allows us to estimate a sheet resistance of ~ 1200 $\Omega$sq$^{-1}$ and a mobility of ~ 150 cm$^2$V$^{-1}$s$^{-1}$ in ambient conditions, independent of the flake thickness. Alternatively, our theoretical calculations indicate that topologically protected surface states (TPSS) should play a key role in the electronic properties of FL antimonene, which supports our experimental findings. We anticipate our work will trigger further experimental studies on TPSS in FL antimonene thanks to its simple structure and significant stability in ambient environments.