Domestic researchers developed a transparent film using graphene. Graphene is made of carbon atoms connected in a honeycomb structure, making it 200 times stronger than steel and over 100 times better at conducting electricity than copper, earning it the title of "dream electronic material." The transparent film made from graphene absorbs light better as the intensity increases, where the principle is that light is absorbed and reduced as it passes through the film. This film can be used to protect eyes or equipment.
Researchers from the Electronics and Telecommunications Research Institute (ETRI) announced on the 9th that they have developed a transparent film that stably disperses graphene. Until now, graphene had adhesive properties, making it difficult to utilize in industrial settings. To separate graphene, it had to be dispersed mechanically by dissolving polymers in a solvent and then adding a chemical dispersant to keep the graphene from sticking together again. This method had the issue that if the solvent evaporated, the graphene would re-adhere, and its properties could change.
The researchers developed a photocurable colloidal composition that allows graphene to remain stably separated. Photocuring refers to the process where a substance changes from a liquid to a solid when exposed to light. A colloid refers to a state where solid materials less than 1 micrometer (1 µm is one-millionth of a meter) are dispersed in a liquid. Using this photocurable colloidal composition, the researchers explained that graphene can be evenly distributed even without chemical dispersants. It is also possible to store graphene for over a year without precipitation.
The researchers discovered a method to create a solid transparent film from graphene colloidal compositions using light. They made it into an easily processable material while maintaining the properties of graphene. The transparency of the graphene film changes according to light intensity. It can thus be used for laser sensors, protective films, smart optical sensors, and artificial intelligence (AI) optical materials to protect eyes or equipment.
Since colloidal compositions all become graphene transparent films, no pollutants are produced, benefiting the environment. The graphene transparent film can also support continuous mass production, as it is made using light rather than being pressed out with molds. This research was published in the international journal "Composites Part A: Applied Science and Manufacturing." Shin Hyung-cheol, head of the Human Augmentation Research Laboratory at the Electronics and Telecommunications Research Institute, noted, "A path has been opened for easier utilization of graphene," and added, "It will establish itself as an innovative material in optical components and artificial intelligence (AI) application technology fields."
References
Composites Part A (2025), DOI: https://www.sciencedirect.com/science/article/abs/pii/S1359835X24006912