In this blog post, we will look at the possibilities and potential of how graphene can contribute to the development of wearable devices and smart technology.
Have you ever seen the movie “Mission Impossible” or “Minority Report”? In the movie, the main character wears various wearable devices and solves various missions by displaying computer screens in front of his eyes. It seems like a story that is far removed from us, who stare at the small screen of a mobile phone every day and carry around a heavy laptop to write reports. But would you believe that these advanced devices are actually being developed and distributed to the public? In fact, many people are already using smart watches and smart glasses, and blood glucose monitoring devices are widely used in hospitals, and the distribution of wearable devices is already underway. This technological advancement is not just about increasing convenience, but is fundamentally changing the way we live. From personal health management to the entire industry, wearable devices are gradually becoming an essential technology.
There is a material that has accelerated the spread of these wearable devices. It is graphene. Graphene is a material that has stripped away only one layer of graphite, which is a form of carbon that exists as layers of hexagonal shapes stacked together through covalent bonding. Many scientists have made numerous efforts to obtain this graphene, but they have failed time and again. Surprisingly, this revolutionary material was discovered in a truly simple way. In 2004, the British scientists Andre Geim and Konstantin Sergeevich Novoselov were the first to separate graphene from graphite. The tool that the research team used to separate graphene was nothing but scotch tape. When they accidentally stuck scotch tape on graphite and then peeled it off, only one carbon layer remained on the tape. This discovery earned the research team the Nobel Prize in Physics and helped the scientific community take a step forward.
There are several reasons why graphene has been able to leap forward as a next-generation material. First, graphene has very high physical strength. Because carbon is densely connected in a net shape, it is so strong that it is 200 times stronger than steel, which is generally considered to be very strong. In addition, graphene is very flexible. The spatial freedom created inside a single sheet of carbon gives it elasticity, allowing it to maintain its original graphene properties even when its structure changes. Finally, graphene has excellent thermal and electrical conductivity. Graphene has the same band structure as a semiconductor, where the energy gap between the filled valence band and the empty conduction band is small, allowing electrons to easily move to the conduction band. This property makes graphene excellent for transmitting electricity and heat, which is one of the reasons why it is attracting attention as a key material for next-generation electronic devices. In particular, graphene has twice the thermal conductivity of diamond, which is known to have the best thermal conductivity, and graphene has a resistance value that is more than 35% lower than copper, which is currently used as a wire, making it very conductive. Because of these characteristics, graphene is receiving a lot of attention as a next-generation material to replace existing silicon semiconductors.
Because of its many excellent properties, there are endless fields in which graphene can be used. It is used to make flexible liquid crystal displays because it is highly elastic and can maintain its thermal and electrical conductivity even when bent. The wearable devices and rollable computers mentioned at the beginning can also be made using graphene. In particular, indium tin oxide (ITO), which is mainly used to make displays, has the disadvantage of having a small amount of reserves and poor transparency, so it is attracting a lot of attention as a next-generation material to replace it. In addition, because it has excellent electrical conductivity, it can greatly improve the performance of electrodes such as solar cells and fuel cells, and can also be used as a next-generation semiconductor such as ultra-high-speed transistors. For this reason, graphene has the potential to revolutionize various industries as a next-generation material. For example, new graphene-based batteries can be charged faster than existing lithium-ion batteries and can be used for longer due to their higher energy density. Such batteries are expected to make a significant contribution to the development of technologies such as electric vehicles, smartphones, and drones. In addition, graphene-based transparent electrodes are transparent and highly conductive, making them an essential element for future transparent displays and smart window technologies.
Because of all these characteristics, graphene is emerging as a key player in the era of ubiquity, connecting everything in the home. Thin and flexible electronic tags using graphene can connect the objects we own, such as home appliances, cars, and even clothes, to operate as a single integrated system. Such a system will enable the smart home of the future that we imagine. For example, a closet with a graphene tag will recommend clothes to wear today based on weather information, and a refrigerator will automatically check the expiration date of food in the refrigerator using graphene sensors and order the necessary food. In addition, graphene-based smartwatches and health monitoring devices will check the user’s health status in real time and automatically send the data to the doctor.
Let’s go back to the beginning and imagine. In the morning, the screen in front of you automatically tells you the weather and what to do for the day, and the robot automatically prepares breakfast. After eating the breakfast prepared by the robot, you put on your smartwatch connected to your computer and go to work. When you come home at the end of the day, home appliances equipped with graphene sensors greet you and automatically optimize the environment in the house. And when it’s time to sleep, the screen will tell you what to do tomorrow and automatically provide you with the optimal sleeping conditions. All of this may not be just a thing of the distant future. With innovative materials and technologies like graphene, we will be able to make that future we only saw in movies a reality.
