Graphene Composites: Types and Applications Overview
The development of materials is closely tied to the progress of society. As technology advances, there is an increasing demand for materials with superior properties. Traditional materials with singular attributes are no longer sufficient for industrial needs, making the search for materials with excellent comprehensive performance crucial.
Since 2004, when Geim and Novoselov from the University of Manchester isolated single-layer graphene crystals using tape, graphene has become a hot topic in material science. Graphene, essentially a single atomic layer of graphite, boasts a unique two-dimensional structure along with exceptional mechanical, thermal, optical, and electrical properties. As a result, it has become a key component in various functional composite materials. Since Ruoff et al. proposed in 2006 that graphene can be produced on a large scale and at low cost through chemical methods, graphene-based composites have become an important research area. These materials show excellent performance in energy storage, liquid crystal devices, electronic devices, biomedical materials, sensing materials, and catalyst supports, offering broad application prospects.
Research on graphene composites primarily focuses on graphene-polymer composites and graphene-based inorganic nanocomposites. As research deepens, the application of graphene reinforcements in bulk metal matrix composites is also gaining attention. Multifunctional polymer composites and high-strength porous ceramic materials made from graphene have enhanced many special properties of composite materials. Below is a brief introduction to some of the currently applied graphene composites.
1. Graphene-Polymer Composites
Adding a proper amount of graphene to a polymer matrix overcomes the shortcomings of conventional inorganic fillers, which typically require large amounts and cannot balance rigidity, heat resistance, dimensional stability, and toughness. This significantly improves the mechanical, thermal, and rheological properties of polymers. The composite material’s thermal expansion coefficient decreases, and its thermal conductivity increases significantly.
2. Graphene-Based Inorganic Nanocomposites
The presence of inorganic nanoparticles increases the interlayer spacing of graphene sheets to a few nanometers, significantly reducing interactions between graphene layers. Modifying graphene sheets with inorganic nanoparticles provides a novel way to prevent graphene sheet aggregation. Moreover, graphene-based inorganic nanocomposites retain the inherent properties of both graphene and inorganic nanoparticles while producing novel synergistic effects, offering extensive application value.
3. Metal Matrix Graphene Composites
Graphene reinforcements are a major focus due to their excellent electrical, thermal, mechanical, and optical properties. As an ideal reinforcement phase, graphene has a bright future in metal matrix composites. These composites can offset the shortcomings of pure metals by offering superior performance in various aspects compared to single-base materials. Graphene/metal matrix composites (Gr-MMCs) find broad applications in aerospace, automotive, electronics, and military fields.
In summary, graphene can be an essential component in composite materials, producing graphene-based composites with excellent electrical, optical, mechanical, and thermal properties. These materials are widely used in catalysis, high-strength materials, electronics, energy conversion and storage, biotechnology, and biochemical sensors.
Additionally, improving the electrical and thermal conductivity of materials is beneficial for many applications. Some graphene-reinforced elastomers are already available on the market and have been processed into products such as high-performance sports shoes, sporting equipment, bicycle tires, and recyclable floor mats. Folsom Custom Skis (Denver, Colorado) recently incorporated graphene additives into their latest ultra-light carbon fiber composite touring ski series. Based on initial prototypes and tests, the skis were redesigned to fully exploit graphene’s advantages. After mechanical and field testing, graphene-enhanced skis were introduced in 2022 as the UltraLite structure style, applicable to any Folsom ski shape. Besides weight reduction, these skis offer higher strength, enhanced performance, better vibration dampening, and lower delamination risk compared to previous models, as graphene significantly improves adhesion between materials and reinforced epoxy.
The development of graphene composites marks a new milestone in material research. These composites have stable structures and excellent properties, with broad application prospects. Therefore, future research in the field of composite materials should emphasize graphene composites, optimizing them from the perspectives of preparation methods, structure, and properties to promote new developments in material engineering.