Preparation And Properties Of Two-dimensional Material Zirconium Disulfide

The single-layer Zr S₂ has superior electrical properties,and it has a higher upper limit of phonon limited migration（1200cm2/V·s）,which is three times that of the widely studied Mo S₂（340cm2/V·s）.And field effect transistors（TFETs）based on Zr S₂have a higher plate current density（800μA/μm）,which is more than one hundred times that of Mo S₂.Has been widely concerned by the scientific community.However,at present,only scholars have prepared a single layer of Zr S₂ with a size of 1-3μm on a hexagonal boron nitride substrate.In this paper,based on this situation,using chemical vapor deposition method,with Si O₂ as a substrate,to control the preparation of large-size single-layer Zr S₂.The core of this article is to use chemical meteorological deposition（CVD）to control a large area of single layer Zr S₂ on a traditional silicon substrate.The first-principles based on density functional theory is used to calculate the energy band diagram and XRD pattern of single-layer Zr S_2,which is compared with the experimental sample characterization.The main research contents are as follows:1.Use Material Studio 3D software to construct Zr S₂ cells and optimize their geometric structure.The optimized lattice constants are a=3.69092?,b=3.69092?.The energy band diagram of the single layer Zr S₂ is calculated,and the band gap is 1.4e V.From the calculated XRD pattern,the diffraction peaks are observed at 2θof 15.1°（001）,28.0°（100）,and 32.5°（101）,42.5°（102）,50.0°（110）and other places,the comparison of the single layer Zr S₂ characterization results obtained by the experiment is basically consistent,and it is consistent with the Zr S₂ standard card PDF#11-0679.2.A single layer of Zr S₂with a size of 20μm was prepared on the Si O₂ substrate for the first time by CVD,which is much larger than the size of the single layer Zr S₂ prepared by other scholars on the BN substrate.For the first time,the preparation method of placing the zirconium source and the substrate in the temperature-dividing zone was put forward,and the controlled variable method was strictly used.It can control the best conditions for large size and high quality Zr S₂,and characterize and verify it.