Controllable Synthesis Of Vertically Aligned ReS_2?1-x?Se_2x Nanosheets With Tunable Chemical Compositions And Bandgaps

Two-dimensional?2D?layered materials have been extensively studied in recent years beccause of their excellent electrical and optical properties.Graphene is one of the most intensively studied 2D layered materials,and has been widely applied in various fields.Moreover,as a member of 2D layered materials family,transition-metal chalcogenides?TMDs?have recently attacted trimendious research interest due to its numorous properties that are different from graphene.TMDs has potential applications in optolectronic devices,field effect transistor and electrocatalysts.Chemical vapor deposition?CVD?has became an important method for the synthesis of 2D TMDs.CVD method possesses wide adaptability and diversity,and can realize chemical tailoring at the atomic or molecular level.Meanwhile,the purity is very high for the materials obtained via CVD method.In this thesis,the controllable synthesis of vertically aligned ReS₂ nanosheets?NSs?and ReS_2?1-x?Se_2xx nanosheets'bandgap modulation have been studied.In addition,the sensors based on ReS_2?1-x?Se_2x?x=0 and x=0.47?has been constructed.Our work is mainly focused on the following aspects:?1?The vertically aligned ReS₂ nanosheets had been synthetized via CVD method.The impact of growth time on the morphology of ReS₂ nanosheets was systematically studied.?2?The vertically aligned ReS_2?1-x?Se_2x nanosheets were obtained by selenizing the vertically aligned ReS₂ nanosheets.Moreover,the structure,morphology and optical properties of the ReS_2?1-x?Se_2x nanosheets were comprehensively characterized.?3?Finally,the performances of sensors based on the ReS_2?1-x?Se_2x?x=0 and x=0.47?nanosheets were tested,and the device performance with different Se contents was comparatively studied.