As a typical compound of tungsten, tungsten diselenide (WSe2) has excellent mechanical, electrical, optical, and magnetic properties due to its special crystal structure. It is widely used in aerospace, military and defense, medical equipment, and other fields. In this article, let’s take a closer look at the properties and uses of tungsten diselenide (WSe2).
Tungsten diselenide is a layered inorganic compound with a hexagonal structure similar to molybdenum disulfide (MoS2). Each tungsten atom is bound to six selenium atoms in a prism coordination pattern, and each selenium atom is bound to three tungsten atoms in a pyramidal configuration. The bond length between tungsten and selenium is 2.526 Å, and the bond length between selenium and selenium is 3.34 Å, and the layers are combined by van der Waals forces.
Tungsten diselenide is a black or gray solid powder with a molar mass of 341.76g/mol, a hexagonal layered crystal structure, a density of 9.32g/cm3, and poor thermal conductivity. Its thermal conductivity is about one hundred thousandth of that of a diamond with better thermal conductivity.
In addition, WSe2 has a band gap between wide gap semiconductors and zero band gap graphene, and has excellent electrical and optical properties as well as high quantum yield.
Its preparation can be divided into the following steps:
First, a magnetron sputtering method is used to deposit tungsten films of different thicknesses on the substrate, and part of the tungsten films are annealed for use. Then, the annealed and unannealed tungsten film samples and a certain amount of selenium powder are packaged and placed in a vacuum quartz tube. After that, the packaged sample is placed in a tube furnace, heated, and selenized to obtain the product.
It can be well used in photovoltaic devices and ultra-thin LEDs, mainly because the band gap of WSe2 is 1.35 eV, and it has good optical properties and physical and chemical stability.
Besides, it can be used as a lubricant additive. WSe2, like molybdenum disulfide and tungsten disulfide, is a low-dimensional layered structural material with a smaller friction coefficient.
Thank you for reading our article and we hope it can help you to have a better understanding of the properties and uses of tungsten diselenide (WSe2). If you want to learn more about tungsten, we would like to advise you to visit Advanced Refractory Metals (ARM) for more information.
Headquartered in Lake Forest, California, USA, Advanced Refractory Metals (ARM) is a leading manufacturer & supplier of refractory metals & alloys across the world. It provides customers with high-quality refractory metals & alloys such as molybdenum, tantalum, rhenium, tungsten, titanium, and zirconium at a very competitive price.
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