Transparent and Electrically Conductive Films from Chemically Derived Graphene

The research interest in graphene based materials, especially for high quality graphene emerged due to its unique electronic and mechanical properties. Some exceptional properties are the high charge carrier mobility at room temperature of 2.5x105 cm2V-1s-1, the thermal conductivity of 5000 WK-1m-1 and the mechanical stiffness of 1 TPa. Moreover, in electronic devices graphene will open up the possibility for a post silicon age. These properties are valid for graphene with a defect-free structure. For large-scale preparation of graphene a processible and versatile precursor called graphene oxide is utilized. (Compton & Nguyen, 2010). In this article, a historical overview will be given to elucidate the development of graphene and especially the precursor graphene oxide, its structure in the oxidized and reduced state. Moreover the synthetic methods for graphene preparation will be contemplated. One discipline in graphene research is the preparation of transparent and electrically conductive coatings for the substitution of commonly used transparent conductors as indium tin oxide (ITO), which is currently used for touch screen applications and transparent electrodes. One essential disadvantage of ITO is its brittleness that excludes applications in flexible or wearable electronics. Furthermore, the performance of such potentially flexible transparent and conductive coatings in dependants of its preparation method will be reviewed using graphene as the reference material. Besides, graphene based transparent coatings will be compared with other suitable transparent coatings.