What is Graphene with High Quality?
Graphene is a two-dimensional material composed of carbon atoms arranged in a honeycomb structure. Graphene is not only a single-layer carbon atomic material, but also a basic unit of carbon materials of other dimensions: a zero-dimensional fullerene can be obtained by wrapping graphene into a spherical shape, a one-dimensional carbon nanotube can be obtained by rolling graphene into a tube shape, and a three-dimensional graphite structure can be obtained by stacking graphene into layers. The quality of graphene material determines the application range of graphene. High-quality graphene materials should possess the advantages of large specific surface area, intentional optical properties, good electrical and thermal conductivity, high mechanical strength, and high carrier concentration mobility. High-quality graphene materials have important application prospects in the fields of electronic information, energy, functional materials, biomedicine, energy conservation and environmental protection.
Figure 1. Schematic diagram of graphene forming other carbon materials
What are the Application of Graphene with High Quality?
- Graphene with High Quality for Electronic Field: In electronic products and devices, graphene conductive coating materials are widely used because of their extremely low sheet resistance and extremely high light transmittance. The surface resistance of graphene material can be as low as 30 Ω, the light transmittance is as high as 97.7%, and it has very good mechanical elasticity and chemical stability. Therefore, graphene materials have become an excellent substitute for indium tin oxide (ITO). In optoelectronic devices, the detection wavelength of graphene photodetectors is wider than that of traditional semiconductor photodetectors, ranging from ultraviolet to infrared. Therefore, changing the working bandwidth of graphene photodetectors can be used to prepare high-speed information transmission materials. In addition, the electronic conductivity in graphene is much greater than that of general semiconductors, which gives graphene crystals a greater advantage over silicon wafers. Transistors made from graphene are not only small and low-cost, but also have very low voltages for switching on and off, making them more sensitive, faster, and less power-hungry.
- Graphene with High Quality for Biosensors: Graphene has good electrical conductivity, and various biosensors based on graphene-modified electrodes have been widely studied and applied to the detection of biological substances. For example, combining graphene and nanomaterials to prepare composite materials can achieve high-sensitivity detection of enzyme-free organisms, and has the advantages of high stability and strong selectivity.
- Graphene with High Quality for Hydrogen Storage Material: Graphene is a two-dimensional structure with a single-layer atomic thickness. It has the advantages of high electronic conductivity, large specific surface area, good chemical stability, etc., and has strong adsorption of hydrogen, which can be used as a hydrogen storage material.
- Graphene with High Quality for Catalyst Support Material: Graphene with high quality has a larger theoretical specific surface area and better electronic conductivity. In the electrochemical reaction, the graphene support can not only improve the dispersion of the catalyst nanoparticles on its surface, but also make the electrode and the electrolyte have a larger contact area, which is conducive to the progress of the electrochemical reaction, thereby improving the catalytic performance of the catalyst.
- G. Deokar, J. Avila, I. Razado-Colambo, J.-L. Codron, C. Boyaval, E. Galopin, M.-C. Asensio, D. Vignaud. Towards high quality CVD graphene growth and transfer [J]. Carbon, 2015, 89, 82-92.