Synthesis and characterization of a pure 2d antimony film on au(111)

Abstract

The synthesis of antimonene and related 2D Sb films on top of metallic substrates has recently become a very active subject due to the strong spin-orbit coupling and the envisaged topological properties of this novel material. Gold has been used as a standard substrate for other 2D films, but in the case of Sb, no success has yet been reported mainly due to the formation of AuSb2 surface alloy. In this work, we have used low energy electron diffraction, time-of-flight direct recoil spectroscopy, X-ray photoemission spectroscopy, and scanning tunneling microscopy together with density functional theory calculations to provide a full characterization of the growth and the structural properties of Sb deposited on Au(111). We show that the controlled deposition of Sb on Au(111) at room temperature results in a surface alloy at submonolayer coverage, but around 1 ML a pure 2D Sb film with a (3 0) 1 2 commensurate structure is achieved. The obtained 2D material has high stability and can be produced not only by direct deposition of Sb over the clean Au substrate but also by starting from a thicker Sb film followed by annealing of the sample at about 500 K, which is easier and reliable for potential applications.