In a new development, a new method to make large sheets of atomically thin, high-quality graphene has been devised. The development could lead to creation of flexible, ultra-lightweight solar cells. And, furthermore, this could lead to development of new classes of light-emitting gadgets and other thin-film electronics.
Developed at MIT, the manufacturing process should be easy to scale up for industrial production. The process involves an intermediate layer of material that is key to the success of the technique. The use of the intermediate layer enables the ultra-thin graphene to be lifted from its substrate. This allows for rapid roll-to-roll manufacturing.
Array of Applications of Graphene Electrodes
Nonetheless, in recent years, in thin-film electronics, the discovery of a way to make thin, stable, large-area transparent electrodes is a major quest. These electrodes find use for a number of applications in optoelectronic devices. On the other hand, at present, the standard material used for such electrodes is indium tin oxide –a material based on rare and expensive chemical metals.
Meanwhile, several research groups have worked to find a replacement for indium tin oxide. Such efforts are focused to develop organic as well as inorganic candidate materials. Graphene – a form of pure carbon that has atoms arranged in a flat hexagonal array features extremely superb mechanical and electrical properties. Despite this, graphene is physically flexible, vanishingly thin, and is made from abundantly available inexpensive material.
Also, graphene can be easily expanded in the form of large sheets using chemical vapor deposition (CVD), wherein copper is used as seed layer. Meanwhile, for device applications of graphene, the trickiest part is to find ways to loosen it from its native copper substrate.
Known as graphene transfer process, this process tends to cause a web of wrinkles, tears, and defects in the sheet.