Since the first single-layer graphene was prepared in 2004, many scientists have started to study graphene. Graphene has become a shining star in the field of materials and condensed matter physics. Graphene has broad application prospects in many fields due to its extraordinary properties.
Composite material
Due to its extremely high mechanical and electrical properties, graphene is considered to have extensive research prospects as a polymer matrix-enhanced functional additive. The addition of graphene is not only beneficial to the electrical properties and thermal conductivity of the polymer matrix, but also has great significance for increasing the glass transition temperature and improving the mechanical properties of the composite material.
Nanoelectronics
In 2005, researchers found that graphene has a high carrier mobility (approximately 10cm/V·s) that is 10 times that of commercial silicon wafers at room temperature, and is very little affected by temperature and doping effects, showing room temperature sub Micrometer-scale ballistic transmission characteristics (up to 0.3m at 300K), this is the most prominent advantage of graphene as a nanoelectronic device, making it a very attractive room temperature ballistic field effect tube in the field of electronic engineering. The larger Fermi speed and low contact resistance help to further reduce the device switching time, and the ultra-high frequency operation response characteristics are another significant advantage of graphene-based electronic devices. In addition, graphene is reduced to the nanometer scale and even a single benzene ring also maintains good stability and electrical properties, making it possible to explore single-electronic devices.
Instead of silicon to produce supercomputers
Graphene is currently known as the most conductive material. This characteristic of graphene is particularly suitable for high-frequency circuits. High-frequency circuits are the leaders of the modern electronics industry. As engineers are trying to fill more and more information in signals, they are required to use higher and higher frequencies. The higher the operating frequency in the circuit, the more heat High, so the promotion of high frequency is greatly restricted. Due to the emergence of graphene, the development prospect of high-frequency enhancement seems to have become infinitely broad. This makes it also has huge application potential in the field of microelectronics. Researchers even see graphene as an alternative to silicon, which can be used to produce future supercomputers.
Super capacitor
Because graphene has a very high theoretical specific surface area, it belongs to a single layer of graphite crystal material that exists independently in structure, so both sides of the graphene sheet can be negatively charged to form an electric double layer. Due to the structural instability and potential functional groups, graphene prepared by chemical methods is prone to form macroscopic aggregates, and the graphene sheets are randomly stacked and distributed with each other, resulting in a reduction in the area of the effective electric double layer. Solving the agglomeration under its macro conditions effectively increases its surface area, and it is possible to obtain a specific capacitance higher than that of porous carbon. Due to the peculiar wrinkle and superposition effect of graphene sheets, the nano-holes and nano-holes that can be formed are conducive to the diffusion of electrolyte, so graphene-based supercapacitors have good power characteristics.
Solar battery
In 2010, researchers first covered graphene on traditional single-crystal silicon materials, and found that it has excellent photoelectric conversion performance. Such a simple solar cell model, after optimized and improved, the photoelectric conversion efficiency can reach more than 10%. The graphene-silicon model can be further extended to the structure of graphene and other semiconductor materials. This model that can combine graphene with traditional materials has an important role in promoting the practical application of graphene.
Photon sensor
Graphene can also appear on the larger market as a photon sensor. This sensor is used to detect information carried in optical fibers. This role has always been assumed by silicon, but the era of silicon seems to be coming to an end. The research team disclosed the graphene photodetector they developed for the first time, and what people want to look forward to next is the graphene-based solar cell and liquid crystal display. Because graphene is transparent, the electric plates made with it have better light transmission than other materials.
Gene sequencing
Because the thickness of conductive graphene is less than the distance between adjacent bases in the DNA chain and there are electronic fingerprints between the four bases of DNA, graphene is expected to achieve direct, fast, and low-cost gene electronic sequencing technology .
Hydrogen storage
The combination of graphene and carbon nanotubes can form a three-dimensional network structure for hydrogen storage. The calculation method shows that under the condition of doping lithium ions, the atmospheric pressure hydrogen storage capacity can reach 41g/L. Ghosh et al. used a material obtained by exfoliating graphite oxide and converting nano-diamonds to 77K to adsorb 1.7% of gas under one atmosphere of pressure. The amount of hydrogen adsorbed changes linearly with the change of the surface. At 100 atmospheres, the adsorption capacity at 298K can reach or even exceed 3%, indicating that the single-layer graphene has greater hydrogen storage capacity.
Other applications
Graphene can also be used in transistors, touch screens and other fields, and is expected to help physicists make new breakthroughs in quantum physics research.
Chinese researchers have discovered that bacterial cells cannot grow on graphene, but human cells are not damaged. Using this feature, graphene can be used for bandages, food packaging, and even antibacterial T-shirts.
Photoelectrochemical cells made of graphene can replace metal-based organic light-emitting diodes. Graphene can also replace traditional metal graphite electrodes on lamps, making it easier to recycle.
Graphene can not only be used to develop and manufacture ultra-light aircraft materials as thin as paper sheets, to produce ultra-tough bulletproof vests, but also to make the 23,000-mile-long space elevator that scientists dream of a reality.