Preparation And Photoelectrical Properties Of 2D Antimony And Transition Metal Sulfides

Two dimensional transition metal sulfide(TMDCs)is a material with similar layered structure with graphene.Because of its unique physical properties and potential applications in sensor and nano photoelectric,this material has attracted academic interest.At present,some progress has been made in the research of graphene,MoS2,WS2 and other two-dimensional materials.However,as a typical two-dimensional transition metal sulfide,the WS2 photoelectric properties of the graphene like lamellar structure remain to be further studied.In this work,we prepared two dimensional antimony thin films by using a simple and easy micromechanical stripping method.The electrical stability of antimonene and has been studied.Meanwhile,large area single layer triangular WS2 single crystal and MoS2 thin films were successfully prepared by chemical vapor deposition(CVD),and the MoS2/CsPbBr3 heterojunction devices were made by spin coating CsPbBr3 on the films.Two dimensional antimony was synthesized with micro mechanical stripping method on SiO2/Si(SiO2 thickness 300nm)substrates.The surface morphology,phase structure and performance characterization were studied.The results showed that after two months in the air,the electrical properties of the antimonene device did not change too much,which indicated that antimony can be used as a promising candidate for electric devices.Tungsten sulfide(WS2)were prepared by chemical vapor deposition(LPCVD).We carried out a series of structural components analysis on WS2.It was found that the thickness of the obtained WS2 was about 0.8nm,and it was a monolayer.XPS results displayed that W has two main peaks at 31.8eV and 33.9eV at the binding energy,and there is a weak peak in 37.5eV,which originates from the existence of the W-O bond.The growth process of the WS2 were also studied.And the optimized condition is 850? of substrate temperature,1000? of WO 3 temperature,120? of S temperature,20 sccm of H2 flow,80sccm of Ar flow.The optical-electric properties of the WS2 thin films were also investigated.The results showed that the photodetector of the WS2 demonstrate the photoresoponsivity of 0.33A/W and detectivity of 1.05×1010 Jones with a incident laser of 20?W/cm2.This experiment also uses micro mechanical stripping method and atmospheric pressure chemical vapor deposition method in SiO2/Si(SiO2 thickness 300nm)substrates for antimony ene of large area and high quality,the preparation of(Sb),two(TaSe2),tantalum selenide two tungsten sulfide(WS2)and molybdenum disulfide(MoS2)films,and the samples were a series of surface morphology,phase structure and performance characterization.he test results showed that after two months in the air,the electrical properties of the antimonene device did not change too much(which should be listed in the specific value of the change).MoS2 thin films were prepared by low pressure chemical vapor deposition(LPCVD),and CsPbBr3 was applied to the preparation of MoS2/CsPbBr3 heterojunction devices.The microstructure characterization and optical performance were tested.The results showed that the thickness of the obtained MoS2 is about 0.8nm,the XRD diffraction peak CsPbBr3 is at 15.368 degrees and 30.716 degrees,which indicates that CsPbBr3 shows high degree of crystallinity;By measuring the temperature fluorescence spectra,it can be found that,with the increase of temperature(17K-300K).The PL peaks of CsPbBr3 vary from 550nm to 525nm,and of PL intensity decreases.The PL intensity of CsPbBr3 is greater than that of MoS2/CsPbBr3,and the exciton binding energy is calculated from PL spectrum,and the calculated values are 40.5meV(MoS2/CsPbBr3)and 72.4meV(CsPbBr3),respectively.The MoS2/CsPbBr3 heterojunction has the advantages of high sensitivity(maximum 4.4A/W),high quantum efficiency(up to 302%),large switching ratio(maximum>103),and short response time(rise time 0.72ms,fall time 1.01ms),showing great potential in photoelectron detector.