Graphene has become a hot research topic in the field of materials due to its excellent properties and unique two-dimensional structure.  In this paper, the preparation methods of graphene are reviewed and the advantages and disadvantages of various methods are analyzed and compared. The mechanical, optical, electrical and thermal properties of graphene are briefly introduced.  Graphene-based composites are an important research direction in the application field of graphene. This paper introduces the preparation and application of graphene polymer composites and graphene-based inorganic nanocomposites in detail, as well as the prospect of graphene composites.  

Key words: graphene: Preparation; Performance; Composite material

Graphene is a kind of two-dimensional carbon nano material, which is composed of carbon atoms and SP 2 hybrid orbital.
Graphene has excellent optical, electrical and mechanical properties. It has important application prospects in materials, micro nano processing, energy, biomedicine and drug delivery, and is considered as a revolutionary material in the future. Physicists Andre Geim and Konstantin Novoselov from the University of Manchester, UK, successfully separated graphene from graphite by micromechanical stripping method, so they jointly won the 2010 Nobel prize in physics. The common production methods of graphene powder are mechanical stripping, oxidation-reduction, SiC epitaxial growth, and chemical vapor deposition (CVD).

Graphene has excellent optical, electrical and mechanical properties, and has important application prospects in materials, micro nano processing, energy, biomedicine and drug delivery. Graphene is one of the materials with the highest strength known, but also has good toughness and can be bent. Graphene is the carbon material with the highest thermal conductivity so far because of its excellent thermal conductivity. Graphene has very good optical properties, graphene has very good optical properties, graphene has been widely used in ultrafast photonics. Graphene has the advantages of light weight, high chemical stability and high specific surface area, making it the best candidate for hydrogen storage materials. Due to the characteristics of high conductivity, high strength, ultra light and thin, the application advantages of graphene in aerospace and military industry are also outstanding. At present, the research of graphene composites is mainly focused on graphene polymer composites and graphene based inorganic nanocomposites. With the development of graphene research, the application of graphene reinforcement in bulk metal matrix composites has attracted more and more attention. The multifunctional polymer composite and high-strength porous ceramic material made of graphene enhance many special properties of the composite.