1 Meteorological deposition method is mainly carbon-containing gas (methane, vaguely). Under certain temperature and pressure conditions, carbon atoms attach to the growth base, forming a single-layer carbon structure substance and growing gradually. Advantages: The obtained graphene has a good structure and the size is not limited by raw materials. Disadvantages: complex preparation process and low production efficiency.
Oxidation-reduction method is to oxidize graphite layer by layer with oxidant, and peel off the oxide layer with ultrasonic wave. And then reducing the graphite oxide layer with a reducing agent to obtain graphene. Advantages: low cost and high production efficiency. Disadvantages: The size of graphene is determined by raw materials, and the oxidant and reductant used may pollute the environment.
3 Intercalation method is to fill intercalation substances into the gaps between graphite layers, so as to overcome the van der Waals force between the layers and disperse the layers, thus obtaining graphene. This method is still in the development stage.
Extended data:
Graphene has excellent optical, electrical and mechanical properties, and has important application prospects in the fields of material science, micro-nano processing, energy, biomedicine and drug delivery, and is considered as a revolutionary material in the future. Physicists Andrei Grimm and Konstantin Novoselov of the University of Manchester in England successfully separated graphene from graphite by micromachining, so * * * won the 20 10 Nobel Prize in Physics.
The common methods of graphene powder production are mechanical stripping, redox and SiC epitaxial growth, and the method of thin film production is chemical vapor deposition (CVD). On March 3rd, 2065438, the first automatic production line of graphene organic solar photovoltaic devices in China was started in Heze, Shandong. This project mainly produces graphene organic solar cells (hereinafter referred to as graphene OPV) which can generate electricity in low light, and solves three major solar power generation problems: limited application, sensitive angle and difficult modeling.
1 monolayer graphene
Single-layer graphene refers to a two-dimensional carbon material (hexagonal honeycomb structure) composed of a layer of carbon atoms with benzene ring structure.
2 double graphene
Double-layer or double-layer graphene: refers to a two-dimensional carbon material composed of two layers of carbon atoms which are periodically and closely stacked in different stacking ways (including AB stacking and AA stacking) into a benzene ring structure (that is, a hexagonal honeycomb structure).
3 several layers of graphene
A few layers refers to a two-dimensional carbon material composed of 3- 10 layers of carbon atoms which are periodically and closely packed in a benzene ring structure (i.e. hexagonal honeycomb structure) in different stacking modes (including ABC stacking and ABA stacking). ?
4 Multilayer Graphene
Multilayer graphene, also known as multilayer graphene, refers to a two-dimensional carbon material with a thickness of more than 10 and less than 10nm, in which carbon atoms with benzene ring structure (i.e. hexagonal honeycomb structure) are stacked in different stacking ways (including ABC stacking and ABA stacking).
Carbon element
Carbon is a very common element, which exists widely in the atmosphere and crust in various forms. The understanding and utilization of simple carbon has a long history, and a series of compounds of carbon-organic matter are the basis of life. Carbon is one of the components of pig iron, wrought iron and steel. Carbon can chemically combine with itself to form a large number of compounds, which is an important molecule in biology and commerce. Most molecules in organisms contain carbon.
Existential form
Carbon has various forms, such as crystal element carbon, such as diamond and graphite; There is amorphous carbon such as coal; There are complex organic compounds such as animals and plants; Carbonate, such as marble. The physical and chemical properties of elemental carbon depend on its crystal structure. High hardness diamond and soft graphite have different crystal structures, each with its own appearance, density and melting point.
References:
Baidu encyclopedia-graphene