博文

目前显示的是 七月, 2021的博文

Chemical Deposition Method Preparing Monolayer Tungsten Disulfide

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Monolayer tungsten disulfide is a kind of nano material with layered structure, it has better temperature stability than monolayer disulfide. It has attracted much attention in recent years because of its better optical and electrical properties, in the semiconductor field such as transistors, tungsten disulfide is an indirect bandgap semiconductor, forbidden band width is  2.0eV, it has more space than the application of graphene in the field of electronic tube. At present, the most important methods to prepare monolayer tungsten disulfide in China are three methods: RF sputtering, reactive magnetron sputtering and chemical deposition. In recent years, the research on the preparation of two-dimensional TMDCs by CVD(chemical vapor deposition) method is mainly focused on molybdenum disulfide, because MoS 2  requires lower temperature and it is easy to control the growth process, tungsten disulfide seems much more complex. There are two main ways to prepare tungsten disulfide fi...

Application of Monolayer Tungsten Disulfide Film in Photoelectric Field

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Two dimensional transition metal chalcogenide (TMDCs) is considered as a potential star material for future applications of electronic devices because of its graphene like structure. The current research more semiconductor materials are tungsten disulfide WS 2 , molybdenum disulfide MoS 2 , MoSe 2  molybdenum selenide, WSe 2  tungsten selenide and so on. Among them, WS 2  has the most promising application in electronic devices because of its bipolar electron transport properties. Single layer two W is a kind of layered material similar to graphite with a layer spacing of 0.7 nm. WS 2  is an important photoelectric material. When WS 2  is changed from bulk material to single layer, the material changes from indirect bandgap to direct band gap semiconductor, and the band gap will change from 1.3eV to 2.0eV, which makes the monolayer tungsten disulfide thin films have important potential applications in photoelectric detectors and solar cells. Monolayers of tung...

How to Make Rare Earth Terbium Zinc Tungstate More Dazzling

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Rare earth ions are rich in energy levels, their luminescence wavelengths can change from ultraviolet to infrared. They are often used as luminescent centers in luminescent materials. Metal tungstate is a kind of important inorganic functional materials, including tungsten ore stone structure of zinc tungstate (ZnWO 4 ) is a self luminous material type. WO 4 2-  itself has self excitation fluorescence, emits blue green light under ultraviolet irradiation, and can effectively transfer energy to rare earth ions. Therefore, it is widely concerned that in the chemical industry, the self luminescent tungstate doped rare earth element is the most effective LED light source acquisition scheme to change its fluorescence color. At present, the synthesis methods of rare earth doped ZnWO 4  are sol gel method, combustion method, hydrothermal method and microemulsion method. Hydrothermal synthesis is a commonly used method for the synthesis of green phosphors ZnWO 4 :Tb 3+ . In the proces...

Zinc Tungstate Whisker

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Whisker is a kind of fiber which grows in single crystal form under artificial control. Whisker's  diameter is very small (micron order of magnitude), no defects in the usual materials (grain boundaries, dislocations, voids, etc.).  Its atomic arrangement is highly ordered, so its intensity is close to the theoretical value of the complete crystal. Because the whisker reinforced composites have the potential of high strength, the research and development of whiskers have been paid much attention to. Zinc tungstate whisker is mainly used in metal matrix composites, and it is a key high-tech material. It has been widely used in ceramic cutting tools, space shuttles, automobile parts, chemical industry, machinery and energy production.  Zinc tungstate has a better scintillation performance than the currently widely used scintillation crystal, but also has the characteristics of not deliquescence and low price, and is a very promising scintillation crystal. The size of zinc ...