This blog post explores how graphene can transform electronics and various future industries, focusing on its structure and properties.
Science Fiction Made Real: The Dream Material “Graphene”
Mr. ○○ starts his morning listening to sounds from a thin display. This display informs him of his daily schedule and even today’s weather. He has nothing to worry about on his commute either, as this display also serves as his navigation system. Upon arriving at the office, he bends the display and wraps it around his arm. This smart display not only functions as a watch but also monitors his health status. His boyfriend calls him via this display. He says he’ll arrive soon and asks her to wait at the coffee shop. ○○ unfolds the display she’s been wearing like a watch and passes the time watching a movie.
Scenes once only seen in science fiction movies are now becoming reality. The key technology making this possible is graphene. Graphene is gaining attention as a next-generation material, surpassing existing materials in various properties such as electrical conductivity, strength, and flexibility.
What is graphene?
So what exactly is graphene, and what properties enable it to make such innovative technologies possible? Graphene is a material composed of a two-dimensional plane of carbon atoms arranged in a honeycomb structure. This material has already proven its practical potential in semiconductors, displays, and ultra-strong fibers, drawing significant attention. Graphene is a thin film of carbon measuring nanometers (10⁻⁹m) in size, serving as the fundamental structural unit of graphite. Graphite consists of multiple stacked layers of graphene; separating these layers to obtain a single layer yields graphene.
Since graphene’s theoretical existence was proposed in 1947, scientists attempted various methods to extract it from graphite but faced prolonged failure. However, in 2004, Professor Andre Geim and Dr. Konstantin Novoselov at the University of Manchester, UK, successfully isolated graphene using a simple method. Their method involved repeatedly sticking a piece of graphite to Scotch tape and peeling it off to obtain graphene. For this research, the two scientists were awarded the 2010 Nobel Prize in Physics.
Properties of Graphene
Graphene can be applied in various industries due to its unique physical and chemical properties. It is particularly noted for its exceptional electrical conductivity, surpassing even metals. While metals generally conduct electricity better than non-metals, graphene, despite being a non-metal, exhibits outstanding conductivity due to its special carbon bonding structure.
The flow of current means electrons move within the material. In graphene, the bonds between carbon atoms consist of σ (sigma) bonds and π (pi) bonds. σ bonds are strong bonds that make electron movement difficult, but electrons in π bonds can move freely, enhancing electrical conductivity. Crucially, graphene features these π bonds throughout its entire structure, forming large orbitals that allow electrons to move freely across the entire sheet.
Graphene is also remarkable for its strength. Despite being only 0.35nm (nanometers) thick, it is 200 times stronger than steel. Furthermore, its thermal conductivity is exceptional, exceeding that of diamond by more than twofold. This offers significant potential for solving heat dissipation issues in advanced electronic devices. Furthermore, graphene possesses flexibility and transparency, making it an ideal material for various electronic displays and wearable devices.
Applications of Graphene
The potential of graphene is limitless. Its application in the semiconductor industry is highly anticipated, promising revolutionary advancements that could potentially replace conventional silicon. Thanks to its thin and flexible properties, graphene is expected to play a crucial role in developing technologies like foldable displays, wearable computers, and transparent electrodes.
Graphene can also play a vital role in energy storage devices. Research is exploring its potential to extend battery life and reduce charging times for electric vehicle batteries and portable electronic devices. This is possible due to graphene’s high electrical and thermal conductivity, which can significantly improve energy efficiency.
Graphene is also attracting considerable attention in the life sciences. Its robust physical properties and biocompatibility make it suitable for medical applications like artificial organs and biosensors, with particularly promising potential for innovative drug delivery systems.
Limitations of Graphene Utilization
However, despite its outstanding properties, graphene still faces several challenges in commercial production and application. Carbon nanotubes, similar to graphene, also received immense attention initially but faced difficulties in mass synthesis at the desired size and shape, delaying commercialization. Similarly, mass production and quality control of graphene remain challenging with current technology.
However, research to overcome these issues is actively underway worldwide. Hope for large-scale graphene production is growing, especially with the development of various techniques like chemical vapor deposition (CVD). Sungkyunkwan University in Korea has also recently achieved success in developing high-performance graphene transparent electrodes, further advancing the potential for graphene commercialization.
Conclusion
Graphene is regarded as one of the most promising new materials discovered to date, with many researchers viewing it as a critical material capable of revolutionizing future industries. Although technical hurdles remain before graphene reaches commercialization, scientists’ efforts and diverse technological advancements suggest its practical application is not far off. Soon, we will encounter graphene in reality, not science fiction, through next-generation technologies that are thinner, stronger, and more flexible.
