Characteristics and applications of single-layer graphene

Overview of few layer graphene

Single-layer graphene is a two-dimensional planar honeycomb graphite composed of a single layer of carbon atoms. The sp2 covalent bond between each carbon atom makes it the thinnest but hardest material in the world (the breaking strength is about 200 times that of steel). It is almost completely transparent and only absorbs 2.3% of light; its thermal conductivity is as high as 5300 W/m. K is higher than carbon nanotubes and diamonds; the resistivity is only about 0.96×10-6 Ω. cm, lower than copper and silver, is currently the world's smallest resistivity material; graphene has a large specific surface area (2630 m2/g). The new feature of graphene is that in the absence of any doping, the Fermi level is located at the junction of the conduction band and the valence band. The effective mass of the electron' is zero at this time, and the carrier appears as a Dirac with a mass of zero. Fermions have excellent carrier conduction characteristics and can carry 108A/cm2 and current densities up to 200,000 cm2/V. The carrier mobility of s (higher than carbon nanotubes and silicon crystals), the speed is 1/300 of the speed of light; in the absence of carrier transport, graphene still has conductivity σ=e2/h, graphene The resistance value of will change with the change of the applied vertical value electric field, which is called the bipolar field effect; it does not conform to the Bonn-Oppenheim approximation in quantum mechanics and can be observed at room temperature. Its normal temperature Hall effect expands the original temperature range ten times, showing unique carrier characteristics and excellent electrical quality. The unique electronic structure of graphene also provides a more convenient means for verifying the relativistic quantum electrodynamic effects that are not easily observed in particle physics.

Few layer graphene refers to a type composed of 3-10 layers of carbon atoms that are periodically and closely packed in a benzene ring structure (that is,hexagonal honeycomb structure)stacked in different stacking methods (including ABC stacking,ABA stacking,etc.)Two-dimensional carbon material.

Singlelayer graphene powder has a two-dimensional structure of a new carbonaceous material.Graphene powder has excellent electrical, thermal and mechanical properties.

The surface area of the single-layer graphene powder produced by our company is very large,500~1200m2/g.

Single layer graphene

Single layer graphene purity::>99.3wt%

Single layer graphene single-layer ratio:97%

Single layer graphene thickness: 0.55nm-1.2nm

Single layer graphene diameter:1μm-12μm

Single layer graphene specific surface area: 500-1200m2 / g

Single layer graphene color:black

Single layer graphene conductivity: 1000-1500 S / M

COA of single layer graphene products: C = 99.6%,O<0.4%

Few layer graphene applications

With the gradual breakthrough of mass production and large-size problems, the industrial application of graphene is accelerating.Based on existing research results,the first commercial applications may be mobile devices,aerospace,and new energy. Battery field.Graphene has a special significance for basic research in physics.It enables some quantum effects that can only be demonstrated theoretically before can be verified through experiments.In two-dimensional graphene,the mass of electrons does not seem to exist.This property makes graphene a rare condensed matter that can be used to study relativistic quantum mechanics – because massless particles must move at the speed of light Therefore,it must be described by relativistic quantum mechanics,which provides theoretical physicists with a new research direction:some experiments that originally needed to be carried out in giant particle accelerators can be carried out with graphene in small laboratories.Zero energy gap semiconductors are mainly single-layer graphene,and this electronic structure will seriously affect the role of gas molecules on its surface.The function of single-layer graphene's enhanced surface reactivity compared with bulk graphite is demonstrated by the results of graphene hydrogenation and oxidation reactions,indicating that the electronic structure of graphene can modulate its surface activity. In addition, the electronic structure of graphene can be correspondingly changed by the,induction of gas molecule adsorption,which not only changes the concentration of carriers,but also can be doped with different graphenes.

1.Sensor

Graphene can be made into a chemical sensor.This process is mainly done through the surface adsorption properties of graphene. According to the research of some scholars,the sensitivity of graphene chemical detectors can be compared with the limit of single molecule detection. Graphene's unique two-dimensional structure makes it very sensitive to the surrounding environment.Graphene is an ideal material for electrochemical biosensors. Sensors made of graphene have good sensitivity for detecting dopamine and glucose in medicine.

2.Transistor

Graphene can be used to make transistors.Due to the high stability of the graphene structure, this type of transistor can still work stably on the scale of a single atom.In contrast,the current silicon-based transistors will lose their stability on the scale of about 10 nanometers; the ultra-fast reaction speed of electrons in graphene to the external field makes the transistors made of it can reach Very high operating frequency.For example, IBM announced in February 2010 that it would increase the operating frequency of graphene transistors to 100 GHz,which exceeds that of silicon transistors of the same size.

3.Flexible display

At the Consumer Electronics Show, flexible screens have attracted much attention and become the development trend of mobile device displays in the future. The future market of flexible display is broad,and the prospect of graphene as a basic material is also promising.South Korean researchers have produced for the first time a flexible transparent display composed of multilayer graphene and a glass fiber polyester sheet substrate. Researchers from South Korea's Samsung and Sungkyunkwan University have fabricated a piece of pure graphene the size of a TV on a 63 cm wide flexible transparent glass fiber polyester board. They said that this is by far the largest "bulk" graphene block. Subsequently,they used the graphene block to create a flexible touch screen.Researchers say that in theory,people can roll up their smartphones and pin them behind their ears like a pencil.

4.New energy battery

New energy batteries are also an important area of graphene's earliest commercial use.The Massachusetts Institute of Technology in the United States has successfully developed flexible photovoltaic panels with graphene nano-coatings on the surface, which can greatly reduce the cost of manufacturing transparent and deformable solar cells.Such batteries may be used in night vision goggles,cameras and other small digital Application in equipment. In addition, the successful development of graphene super batteries has also solved the problems of insufficient capacity and long charging time of new energy vehicle batteries,which has greatly accelerated the development of the new energy battery industry.This series of research results paved the way for the application of graphene in the new energy battery industry.

5.Desalination

Graphene filters are used more than other desalination technologies.After the graphene oxide film in the water environment is in close contact with water, a channel with a width of about 0.9 nanometers can be formed, and ions or molecules smaller than this size can pass through quickly. The size of the capillary channels in the graphene film is further compressed by mechanical means,the pore size is controlled,and the salt in the seawater can be filtered efficiently.

6.Hydrogen storage materials

Graphene has the advantages of light weight,high chemical stability and high specific surface area,making it the best candidate for hydrogen storage materials.To

7.Aerospace

Due to the characteristics of high conductivity, high strength,ultra-light and thin, the application advantages of graphene in the aerospace and military industry are also extremely prominent. In 2014,NASA developed a graphene sensor used in the aerospace field,which can detect trace elements in the atmosphere at high altitudes and structural defects on spacecraft. Graphene will also play a more important role in potential applications such as ultralight aircraft materials.

8.Photosensitive element

The new type of photosensitive element using graphene as the material of the photosensitive element is expected to have a special structure to increase the sensitivity by thousands of times compared to the existing CMOS or CCD,and the energy consumption is only10%of the original. It can be used in the field of monitor and satellite imaging,and can be used in cameras, smart phones,etc. To

9.Composite materials

Graphene-based composite materials are an important research direction in the field of graphene applications.They have shown excellent performance in the fields of energy storage, liquid crystal devices,electronic devices,biological materials, sensing materials and catalyst carriers,and have broad application prospects .At present,the research of graphene composite materials mainly focuses on graphene polymer composites and graphene-based inorganic nanocomposites.With the deepening of graphene research,the application of graphene reinforcements in bulk metal-based composites People are paying more and more attention. Multifunctional polymer composite materials and high-strength porous ceramic materials made of graphene enhance many special properties of composite materials.To

10.Biology

Graphene is used to accelerate the osteogenic differentiation of human bone marrow mesenchymal stem cells,and it is also used to make biosensors for epitaxial graphene on silicon carbide.At the same time,graphene can be used as a nerve interface electrode without changing or destroying properties such as signal strength or scar tissue formation.Due to its flexibility,biocompatibility and conductivity,graphene electrodes are much more stable in vivo than tungsten or silicon electrodes.Graphene oxide is very effective in inhibiting the growth of E.coli without harming human cells.

Low layer graphene price

China also has unique advantages in graphene research.From a production perspective,graphite,which is a raw material for graphene production,has abundant energy storage and low prices in my country. It is precisely seeing the application prospects of graphene that many countries have established graphene-related technology research and development centers to try to commercialize graphene,and then obtain potential application patents in industry, technology,and electronics-related fields.For example,the European Commission has set up a special research and development plan for graphene as the"emerging flagship technology project in the future,"and allocated 1 billion euros in the next 10 years.The British government has also invested in the establishment of the National Graphene Institute(NGI)in an effort to make this material available from the laboratory to the production line and market in the next few decades.

The price of few-layer graphene varies randomly with production costs, transportation costs, international conditions, exchange rates, and market supply and demand for few-layer graphene. Tanki New Materials Co. ,Ltd aims to help all industries and chemical wholesalers find high-quality products by providing a full range of products. If you are looking for a few-layer graphene product, please contact us for the latest price.

Supplier of few layer graphene

As a global supplier of few-layer graphene, Tanki New Materials Co.,Ltd. has extensive experience in the performance,application and cost-effective manufacturing of advanced and engineered materials. The company has successfully developed a series of powder materials(including oxides,carbides,nitrides,single metals,etc.)high-purity targets,functional ceramics and structural devices,and provides OEM services.