Graphene is a single-layer carbon atom surface material peeled off from graphite material. It is a two-dimensional structure of carbon and is the thinnest but also the hardest nanomaterial. 0.335 nanometers, it is harder than diamond and weighs almost zero. It transfers electrons faster than any known conductor at room temperature and can be used to make transparent touch screens, light panels and even solar cells.
What are the application areas of graphene biomass?
8 to 10 hours. According to electronic enthusiasts' demands, fast charging takes 2-3 hours and slow charging takes 10-12 hours, except in special circumstances, it takes not less than 8-10 hours. Charging graphene 60 depends on the output power of the charger and the charging efficiency of the battery. It depends on factors such as magazine flow and tank ageger. It is also affected by factors such as ambient temperature.
Basic characteristics of graphene
Biomass graphene is actually graphene, but the preparation method and source are different. It is made from biomass (straw, lignin, etc.) as raw material. The use of graphene prepared by other physical and chemical methods is the same as that of graphene prepared by other physical and chemical methods. Just like edible oils, some are produced by pressing and others by biological extraction. All products are oils and can be consumed.
Graphene (graphene) is a two-dimensional crystal with a single atomic thickness separated from the graphite material and composed of carbon atoms. In 2004, physicists Andre Geim and Konstantin Novoselov from the University of Manchester in the United Kingdom successfully separated graphene from graphite and confirmed that it couldto exist alone. It is for this reason that they jointly won the 2010 Nobel Prize in Physics.
Graphene is both the thinnest and strongest material, with a breaking strength 200 times superior to that of the best steel. At the same time, it has very good elasticity and can stretch up to 20% of its own size. If a piece of graphene with an area of 1 square meter is used to make a hammock, its weight is less than 1 milligram and it can support a one-kilogram cat.
The most promising application of graphene at present is to become a substitute for silicon, to manufacture ultra-miniature transistors and to be used to produce future supercomputers. According to relevant expert analysis, computer processors will run hundreds of times faster if graphene is used instead of silicon.
Moreover, graphene is almost entirelytransparent, absorbing only 2.3% of light. On the other hand, it is so dense that even the smallest gas atoms (helium atoms) cannot penetrate it. These characteristics make it very suitable as a raw material for transparent electronic products, such as transparent touch screens, electroluminescent panels and solar panels.
As the thinnest, hardest, and most electrically and thermally conductive new nanomaterial discovered so far, graphene is called "black gold" and the "king of new materials" . Scientists even predict that graphene will be “ethylene”. completely change the 21st century. »
Main applications of graphene:
Graphene has particular effects on fundamental research in physics. In a particular sense, it makes it possible to verify by experiments certain quantum effects which do not could previously only be discussed on paper, such asue electrons ignoring obstacles and making ghostly journeys. But what is even more interesting are its many “extreme” physical properties.
Since there is only one layer of atoms, the movement of electrons is limited to one plane, and graphene also has completely new electrical properties. Graphene is the most conductive material in the world. The speed of the electrons in it reaches 1/300 of the speed of light, far exceeding the speed of the electrons of ordinary conductors.
Incorporating one percent graphene into plastic can give the plastic good electrical conductivity; adding a thousandth of graphene can increase the thermal resistance of plastic by 30 degrees Celsius. On this basis, new thin, light, stretchable and extremely strong materials can be developed for use in the manufacture of cars, planes and satellites.
With the gradual breakthroughs in mass production and large size, the industrial application of graphene is accelerating. Based on existing research results, the first area to reach commercial application could be mobile equipment, aerospace and new energy batteries. the fields.
Flexible screens attracted much attention at the Consumer Electronics Show and became the development trend of mobile device screens in the future. The future market for flexible displays is vast, and the prospects of graphene as a base material are also promising. Data shows that the global demand for mobile phone touch screens in 2013 was around 965 million pieces. By 2015, the demand for large-sized touch screens for tablet computers will also reach 230 million pieces, creating a large market for graphene applications. Researchersof South Korean company Samsung have also created a transparent, foldable display made of multi-layer graphene and other materials, and believe large-scale commercial use is imminent.
On the other hand, new energy batteries are also an important area where graphene was commercialized for the first time. Previously, the Massachusetts Institute of Technology in the United States successfully developed flexible photovoltaic panels with graphene nanolayers on the surface, which can significantly reduce the manufacturing cost of transparent deformable solar cells. This type of battery can be used in small devices such as night. vision glasses and cameras. Application to digital equipment. In addition, the successful development of graphene super batteries has also solved the problems of insufficient capacity and long charging time of vehicle batteries.new energy batteries, greatly accelerating the development of the new energy battery industry. This series of research results pave the way for the application of graphene in the new energy battery industry.
Due to its high conductivity, high strength, ultralight and other characteristics, graphene has outstanding application advantages in aerospace and military fields. Not long ago, NASA in the United States developed a graphene sensor for the aerospace field, capable of detecting trace elements in the Earth's atmosphere at high altitudes and structural defects on spacecraft. Graphene will also play a larger role in potential applications such as materials for ultra-light aircraft.
Graphene has a perfect two-dimensional crystal structure and its lattice is composed of six carbon atoms . The hexagonthat it forms has a thickness of one atomic layer. Carbon atoms are connected by σ bonds and the method of combination is sp2 hybridization. These σ bonds give graphene extremely excellent chemical properties and structural rigidity. Graphene is 100 times stronger than the best steel and even stronger than diamond. In graphene, each carbon atom has one unbonded p electron. These p electrons can move freely in the crystal at speeds up to 1/300 the speed of light, giving graphene good electrical conductivity. Graphene is a new generation of transparent conductive material. In the visible light region, the transmission of four-layer graphene is equivalent to that of traditional ITO film. In other wavelength bands, the transmission of four-layer graphene is much higher than that of four-layer grapheneuches. ITO movie.
Graphene is the thinnest and hardest nanomaterial known in the world. It is almost completely transparent, absorbing only 2.3% of light; its thermal conductivity reaches 5300 W/m·K, higher than that of carbon nanomaterials. The electron mobility of tubes and diamonds at room temperature exceeds 15,000 cm2/V·s, which is higher than that of carbon nanotubes or silicon crystals, while the resistivity is only about 10 to 6 Ω·cm, which is lower than that of copper or silver and has the lowest resistivity in the world. Due to its extremely low resistivity and extremely rapid electronic migration, it is expected to be used to develop a new generation of electronic components or transistors that are thinner and conduct electricity faster. Since graphene is essentially a good transparent conductor, it is also suitable for making touch screens ttransparent, light panels and even solar cells.
The emergence of graphene has caused huge waves within the scientific community. Graphene has been found to have extraordinary electrical conductivity, is tens of times stronger than steel, and has excellent light transmission. Its emergence is expected to spark a revolution in the field of modern electronic technology. In graphene, electrons can move extremely efficiently, whereas traditional semiconductors and conductors such as silicon and copper do not work as well as graphene. Due to the collision of electrons and atoms, traditional semiconductors and conductors release some energy in the form of heat. In 2013, general computer chips wasted 72-81% of graphene's electrical energy. does not get lost, which gives it propertiesexceptionally good.
The unique properties of graphene are closely related to its electronic band structure. Based on independent carbon atoms and using the potential generated by surrounding carbon atoms as disturbances, the energy level distribution of graphene can be calculated using a matrix method. Extending near the Dirac point, one can see that the energy has a linear relationship with the wave vector (similar to the photon dispersion relationship), and a singularity appears at the Dirac point. This means that near the Fermi surface, the effective mass of electrons in graphene is zero, which also explains the unique electrical and other properties of the material.