It’s a staple of futuristic movies - flexible screens that can be rolled up into a scroll, or a wearable computer that fits comfortably against the contours of the human body. We’ve all seen such scenes; the hero whips out a little stack of material, and folds it out to reveal a TV screen, or perhaps it’s a videoconferencing system - useful for taunting a nemesis face to face.
All this and more has become one step closer to reality. Samsung Electronics, Korea’s premier bellwether corporation, has announced the success of a joint research team of Samsung Advanced Institute of Technology (SAIT) and Sungkyunkwan University Advanced Institute of Nanotechnology (SAINT) in developing a new method for the creation of flexible nanogenerators using graphene.
Progress named graphene
Graphene is the name given to a material made of carbon atoms linked together in a tight honeycomb-shaped lattice, which manifests in a transparent, paper-like plane with the width of a single atom. Some stats of this wonder nanomaterial include its characteristic as a chemically stable material, consisting of carbon - an excellent conductor of electricity. It has been said that the electric conductivity rate of graphene is 100 times faster than silicon, the material currently used in semiconductors.
Graphene is also see-through, and remains unchanged through physical distortions such as bending or stretching - a property that makes foldable displays and wearable computers possible, making it a heaven-sent material for next-generation display panels.
An immediate application for graphene is for see-through electrodes and transistors, used to conduct electricity through semiconductors and flat-panel displays. Current see-through electrodes are commonly made of indium tin oxide (ITO), a material that easily breaks or loses its electrical conductivity when bent or stretched. Because ITO needs a hard protective case, it has functioned as a stumbling block for the development of flexible display panels or electronic paper. Moreover, the recent shortage of indium and subsequent price rise has lit a fire under the search for a suitable substitute.
The joint research team of SAIT and SAINT first attracted attention by announcing their breakthrough development of large graphene films last year in an issue of Nature, the influential scientific journal. This finding was hailed as one that opened the doors for widespread use of graphene - a material that, despite promising properties, proved hard to adapt for common use through construction of sizable films.
Recent research has further built on previous findings. The so-called “nanogenerators” developed by the joint research team will self-generate electricity when bent, pressed or shaken - without any outside source of electricity. This has garnered much interest due to its potential for widespread usage in fields such as next-generation display panels, IT product and energy generators.
According to experts, the successful application of graphene into nanogenerators have largely solved the key problem of flexible display screens - namely, source of electricity. The era of rolling display screens, wearable cell phones and flexible touch sensors is within sight.
The widespread application of graphene makes hypothetical dream gadgets within reach, such as a display wrapped around the wrist during the day to be used as a watch or mobile phone, then transformed into a navigation system in the car, then folded out to be used as a PC or TV screen at home.
“We are set to introduce a 30-inch graphene film soon, following last year’s 4-inch-wide model,” said Prof. Hong Byung-hee of the joint research team. This finding has been featured in an April issue of Advanced Materials, an international peer-reviewed scientific journal, to widespread interest.