Graphene is a two-dimensional carbon nanomaterial composed of carbon atoms arranged in a hexagonal honeycomb lattice. It possesses numerous distinctive properties and has attracted extensive research interest across a wide range of fields. Research into graphene dates back to 1948, when Austrian scientists Ruess and Vogt first captured images of a small number of graphene layers using transmission electron microscopy. In 2004, British scientists Andre Geim and Konstantin Novoselov successfully isolated single-layer graphene. This breakthrough attracted widespread attention and earned them the 2010 Nobel Prize in Physics.
Graphene is a two-dimensional allotrope of carbon. Single-layer graphene consists of a single layer of carbon atoms, with each carbon atom connected through sp² hybridization to form a two-dimensional hexagonal honeycomb lattice. The C–C bond length in graphene is approximately 0.142 nm, the bond angle is 120°, and its thickness is approximately 0.35 nm.
Graphene is one of the strongest materials known and exhibits excellent mechanical, electrical, and optical properties. It has low electrical resistivity and outstanding electrical conductivity, and the quantum Hall effect can be observed in graphene at room temperature. Graphene also exhibits optical transparency and nonlinear optical properties.
The chemical reactivity of graphene is primarily concentrated at its edges and planar defects. At high temperatures, it can undergo oxidation or react with oxidizing acids to produce compounds such as CO and CO₂. Graphene can also be functionalized with oxygen-containing groups to form graphene oxide or modified with other functional groups to produce corresponding derivatives.
Graphene can be synthesized through various methods, including mechanical exfoliation, chemical vapor deposition (CVD), oxidation–reduction, and electrochemical processes.
Graphene Flake Content: 5 wt%
Graphene Flake Size: 1–5 μm
Dispersant Content: 0.5 wt%
Water Content: 94.5 wt%
1. Moderate Viscosity and Good Printability
The dispersion has a viscosity of up to 3,000 mPa·s, making it suitable for convenient application and offering good printability.
2. Flexible Formulation
It can be readily blended to prepare water-based coatings at different concentrations, supporting a variety of formulation requirements.
3. Easy Redispersion
The dispersion can be redispersed through mechanical stirring, facilitating handling and processing.
1. Thermal Management Materials
Graphene can be incorporated into thermal management materials for products such as LED lighting fixtures. Depending on the system design, it may help reduce overall system costs. Potential applications also include heat dissipation in smartphones, tablet computers, high-power energy-efficient LED lighting, satellite circuits, and laser systems.
2. Automotive Industry
Graphene has potential applications in automotive lubricants, electric vehicles, automotive night-vision systems, and tires. In battery and vehicle technologies, graphene-based materials are being investigated for their potential to reduce battery weight, extend battery service life, and improve electric-vehicle driving range and charging performance.
3. Energy Materials
Graphene can be used in the development of advanced energy devices, including lithium-ion batteries, supercapacitors, and solar cells.
4. Composite Materials
Graphene can be incorporated into polymers and composite materials to improve selected mechanical, electrical, thermal, or barrier properties, depending on the formulation and application.
5. Coatings
Graphene-based coatings can be applied to various surfaces, including glass and metal, for research into corrosion protection, water resistance, and advanced protective coatings.
6. Conductive Printing and Packaging
Graphene-based materials can support the development of conductive inks and printed electronic products. Their potential advantages include high electrical conductivity, flexibility, compatibility with high-speed printing, and low-temperature curing, making them promising for specialized printed electronics and packaging applications.
