# Research Progress and Applications of 2D Antimonene
## 2 Theoretical Research and Experimental Methods
### Epitaxial Growth
#### 2.4.2 Preparation of Single-Layer Antimonene
X-ray photoelectron spectroscopy measurements were obtained before and after the formation of single-layer antimonene. The results showed that the chemical state of the substrate did not change significantly and there was no chemical interface coupling between antimonene and substrate, that is, the interaction between antimonene and PdTe\({}_{2}\) substrate was very weak. It is also proved that antimonene is stable in air and the morphology and configuration of epitaxial single-layer antimonene are revealed for the first time at atomic scale. That is, single-layer antimonene has high chemical inertness and large band gap, which is a significant advance for electron and optoelectronics technology. In addition to single-layer antimonene on compound substrates, antimonene was also prepared on pure metal substrates such as Ge and Ag. [PERSON] et al. [12] synthesized monolayer and multilayer high quality antimonenes on Ge substrate with only 0.6% lattice mismatch with antimonene and studied the growth parameters. Knudsen cell was used to vaporize antimony crystals at an evaporation rate of 2-700 A/min. The temperature of germanium substrate varied between room temperature and 330 \({}^{\circ}\)C, and the deposition rate and substrate temperature were controlled to obtain the growth parameters of antimonene. The crystal structure of antimony was found when the growth temperature was greater than 200 \({}^{\circ}\)C, as shown in Figure 10a. When the temperature is higher, it is determined that the island presents a more regular shape, as shown in Figure 10c-d. Meanwhile, it is proposed that the high temperature of the substrate will reduce the adhesion coefficient of Sb\({}_{4}\), hindering the nucleation and growth. By keeping the temperature constant and changing the deposition rate, it is determined that when the deposition rate is lower than 50 A/min, 3D cone core is formed first, and then 2D growth occurs around it, thus forming a 3-fold symmetrical clover-like island (Figure 10c). When the deposition rate is 200 A/min, 2D island and 3D island are formed. The growth model of antimonene with high nucleation rate and low growth rate is proposed. The growth dynamics were studied in real time by LEEM and LEED. In addition, STEM (scanning transmission electron microscopy) observations were combined with DFT calculations to study and discuss the Ge-Sb interface, showing that Sb-Ge covalent bonds do not exist. The flexion honeycomb  
Figure 9: Antimonene formed on PdTe\({}_{2}\) substrate: (**a**) Schematic diagram of fabrication; (**b**) STM topographic map, illustration: LEED pattern of antimonene on PdTe\({}_{2}\). The six diffraction spots are due to the (1 \(\times\) 1) structure of antimonene relative to the substrate; (**c**) Single–layer antimonene with atomic resolution STM image, showing graphene–like honeycomb; (**d**) Top view (upper) and side view (lower) of the structure of antimony honeycomb belt buckle; (**e**) The height profile along the middle red line (**b**) shows that the apparent height of the antimonene island is 2.8 Å; (**f**) Line profile corresponding to the blue line in (**c**), revealing periodicity of the antimony lattice (4.13 \(\pm\) 0.02 Å). Reprinted with permission from Ref. [55]. Copyright 2016, John Wiley and Sons. structure of \(\beta\)-2D antimony was measured by in STM and single-layer antimonene was characterized by high crystal quality and uniformity. Finally, the environmental stability of 2D antimony was determined by Raman spectroscopy and XPEEM (X-ray photoemission electron microscopy). The growth parameters of antimonene were investigated. In order to study the properties of the tensile strain of antimonene, antimonene can be prepared on the substrate with large lattice mismatches such as Cu and Ag. [PERSON] et al. [16] prepared antimonene on Cu(111) and Cu(110) substrates and compared the differences of antimonene prepared on different crystal planes.