The research of two-dimensional layered materials has attracted attention of scientists in recent years, especially the rapidly developing graphene nanomaterials, which have the characteristics of high strength, excellent electrical and thermal conductivity, and are widely used in the field of sensors. Graphene is known as the king of new materials. However, graphene is a zero-band-gap two-dimensional material and cannot be used as the channel layer of transistors, which limits its further applications in nanoelectronic devices and photoelectric conversion.
The two-dimensional transition metal material also has a graphene-like structure, and also exhibits extremely excellent physical and chemical properties in the fields of optics, electricity, and sensors. Especially transition metal chalcogenide compounds, especially W Group VI transition metal sulfide-tungsten disulfide.
The single-layer nano-tungsten disulfide material has a two-dimensional ordered layered structure and unique physical and chemical functional characteristics. Its structure is similar to graphene. The transition metal chalcogenide passes through the strong inner layer covalent MS bond, and the weak van der Waals force interlayer Interactions are combined. Its anisotropic layered structure has excellent optical, electronic and mechanical properties, as well as high specific surface area, surface effect, quantum size effect and small size effect, and is widely used in electrical materials, nano sensors, nano catalytic materials, nano lubricating materials and other fields are one of the hot new functional materials studied abroad in recent years.
Nano tungsten disulfide cannot be directly obtained by treating natural ore. Due to its unique two-dimensional nano-material layered structure, the development of highly efficient, environmentally friendly and economical nano tungsten disulfide new functional materials has become a research hotspot. At present, the mainstream preparation schemes of nano tungsten disulfide include mechanical peeling method, hydrothermal method, chemical vapor deposition method, sol-gel method, in-situ surface modification method, etc. Generally speaking, various methods are inadequate. The production cost of tungsten disulfide is relatively high.
1. In the field of biomedical materials: tungsten disulfide can be used as a medical contrast agent in photothermal treatment from now to the future. This is because tungsten disulfide is a layered two-dimensional material with a hexagonal crystal system, due to its strong absorption in the near infrared (NIR) region and good biocompatibility. Recently, researchers have tracked WS2 to assess their positioning in cell and tissue environments, developed multi-functional nano tungsten disulfide two-dimensional materials, and combined with medical diagnosis, imaging and treatment, are widely used in biomedical detection and analysis, cancer treatment, toxicology, cell imaging, antibacterial, etc.
2. In the field of mechanical lubricating materials, tungsten disulfide is a layered two-dimensional material with a hexagonal crystal system. In the WS2 layer, W and S are combined by a strong covalent bond, and between the layers, the SS molecular bonds are weaker. The combination of van der Waals force, the force between the layers is weak, the bond energy is low, and displacement is easy to occur during the friction process, so it has a low friction coefficient. In addition, nano tungsten disulfide can absorb and fill the uneven surface of the material in time, and play a certain role in self-repair. The transition metal nano tungsten disulfide can maintain excellent lubricating performance in the range of -273 - 425 ℃, the performance is significantly better than traditional lubricating oil, can adapt to various high temperature and pressure, high vacuum, high load, high speed, high radiation, strong The harsh conditions such as corrosion and ultra-low temperature are widely used in high-tech fields such as military, aerospace, satellite, and spacecraft. Molybdenum disulfide also has similar properties, but compared to the two, molybdenum disulfide is dwarfed.
In the field of sensor manufacturing materials: dichalcogens include two-dimensional materials that provide excitation properties, with the semi-conductive properties of metals, fluorescence, and fast heterogeneous electron transfer characteristics. The use of sensing materials has also shown a clear trend. For example, some researchers have successfully developed a selective room temperature ammonia sensor using WS2 nanomaterials as the sensing material, which shows good sensitivity and excellent ammonia selectivity at room temperature. The developed ammonia sensor has room temperature for formaldehyde, ethanol, benzene And acetone show excellent selectivity.
3. In the field of catalysis, tungsten disulfide is an indirect semiconductor with a large specific surface area. Like the tungsten oxide material, it can also be used as a photocatalyst, which can absorb energy under visible light irradiation and generate electrons by transition. The transition generates electrons e and holes h. The holes react with water to generate highly reactive and strong oxidizing hydroxyl radicals·OH, which can degrade large organic dyes or organic substances into small organic molecules and inorganic ions. Photocatalyst (photocatalyst) is the main means for mankind to control environmental pollution in the future, and its prospect will be worth looking forward to.
In addition, like other types of tungsten heteropoly acid catalysts, tungsten disulfide can also be used in the petrochemical industry. It has the characteristics of high cracking performance, stable and reliable catalytic activity, long service life, and low toxicity, thermal stability and chemical properties. It has good stability and can be used as an effective hydrotreating catalyst for oilfield hydrocracking and hydrodesulfurization.
4. In the field of optoelectronics, tungsten disulfide is a bipolar semiconductor with the unique characteristics of n-type and p-type semiconductors. Layered tungsten disulfide has a two-dimensional layered crystal structure and has a strong internal planar covalent bond. And the interaction of the outer plane dominated by the weak van der Waals force makes high-quality heterojunctions possible. At the same time, the heterojunction formed by stacking graphene, a special two-dimensional material and layered WS2, also exhibits unique physical properties, which attracts the attention of researchers and greatly promotes the layered micro (nano ) tungsten disulfide in the development of optoelectronics, electronic devices, photovoltaic industry, transistor field. For example, researchers have applied tungsten disulfide to Q-switched erbium-doped pulsed lasers and transistors.
5. In the field of new energy, tungsten disulfide is one of the most anticipated materials. The structure of tungsten disulfide material is similar to graphene, with excellent characteristics of high specific capacity and high specific surface area. Tungsten disulfide has a layered structure connected by a weak van der Waals force, and its size is generally nano-scale, there will be between layers The hollow interior and gap will have a larger space ratio, which can be used for effective hydrogen storage and lithium storage. At the same time, its thermal stability is good, the material can be used repeatedly, and cyclic charge and discharge is an excellent energy storage battery material, so it can be widely used in solar cells, fuel cell anodes, lithium battery anodes, super capacitors, etc. many aspects. For example, China Tungsten Online reported that American scientists produced tungsten disulfide supercapacitors by sol-gel method.
Nano tungsten disulfide seems to be omnipotent, but researchers also believe that its main applications and research in the future will focus on medical, optoelectronics and new energy fields, because whether it is lubrication or catalysts, tungsten disulfide applications not irreplaceable. On the contrary, due to the cost factor of tungsten disulfide at this stage, it must reflect its due value in the high-end field, which is also the future development focus of single-layer nano tungsten disulfide.
TRUNNANO (Luoyang Trunnano Tech Co., Ltd ) is a professional tungsten disulfide manufacturer with over 12 years experience in chemical products research and development. If you are looking for high quality tungsten disulfide, please feel free to contact us and send an inquiry.
