Preparation And Properties Of WSe₂ Nanomaterials

The two-dimensional transition metaldichalcogenides?TMDCs?has attracted extensive attention in recent years because of its extraordinary optical,electrical,magnetic and mechanical properties.It is the material which have a similar structure with thegrapheme,but TMDCs have an adjustable band-gap structures,which can make up for the drawback of grapheme,The two-dimensionaltransition metal dichalcogenides are becoming the hot materials in Optoelectronic devices,sensing,field effect transistor?FET?andelectronics.It is also popular in semiconductor because of the high carrier mobility and the high ratio of switching current.At present,people has made some progress in bulk phase transition metal dichalcogenides,but the study of two-dimensional transition metal dichalcogenides remain to be further.Especially for WSe₂,people also pay more attention to its lubricating property in past,the factors which can influence WSe₂ nano-films structure,profile and photoelectric performance is rarely.This thesis,based on graphene-like WSe₂,focuses on the progress which can influence WSe₂ nano-films structure,profile and the applications of the photoelectric performance.The main contents are as follows:1.The WSe₂ nano-films were prepared by magnetron sputtering and selenization in vacuum.The results indicated that the films were opaque.2.The representation of the films were characterized by X-ray diffraction?XRD?,scanning electron microscopy?SEM?,energy dispersive spectromete?EDS?.Tungsten film annealed or not,the sputtering time of tungsten film,the choice of substrate materials and selenide temperature all can regulate and control the profile.We built a copper electrode and a conductive carbon electrode on the surface of the films,4200A-SCS parameter analytical instrument was used to investigated the electroconductibility of the films,the results show that the films exhibited great conductivity,rectification effect and photovoltaic effect.The corresponging photoelectrochemical tests were carried out by using two-electrode system in CHI600 series electrochemical analyzer,WSe₂ nano-films exhibited a fast response speed,and Al2O3-15-750 sample is faster than that of Al2O3-20-750 sample,The rising time and falling time of Al2O3-15-750 sample were 0.16 s and0.12 s.WSe₂ nano-films have greatphotoelectric characteristics,have potential applications in solar cells and optoelectronic devices.