Two dimensional crystal composed of merely a planer sheet of atoms was once proved nonexistent due to the as-predicted unstable nature. This declaration went out of date along with the discovery of a brand new material: graphene. Graphene is a true 2D crystal which only consists of a layer of carbon atoms connected with each other through sp² bonds. It was found to possess unusual physical, mechanical as well as transport properties that make it a highly attractive material for many applications....[ Read more ]

Two dimensional crystal composed of merely a planer sheet of atoms was once proved nonexistent due to the as-predicted unstable nature. This declaration went out of date along with the discovery of a brand new material: graphene. Graphene is a true 2D crystal which only consists of a layer of carbon atoms connected with each other through sp² bonds. It was found to possess unusual physical, mechanical as well as transport properties that make it a highly attractive material for many applications.

This project is aimed to develop new reliable methods to produce graphene and subsequently evaluate the performance of graphene when used in practical applications. One type of graphene was prepared through chemical reduction of graphene oxide. Highly conductive graphene thin films were then prepared, which could be used as transparent conductors. Various properties of transparent conductors were evaluated, proving that the graphene thin films developed in this study is highly likely to replace current material, indium-tin-oxide (ITO), for transparent conductor.

Another type of graphene was prepared through exfoliation of natural graphite in selected organic solvents. Nanocomposites were fabricated through incorporation of the as-prepared graphene into polystyrene matrix. Thermal stability, modulus, electrical and thermal conductivity of graphene/PS composites, were higher than the neat polystyrene. However, the glass transition temperature was not as good as the neat polymer, which may be related to the absence of chemical functionalization on graphene.

Several chemical functionalization methods were adopted to successfully modify graphite nanoplatelets which consist of multi-layer of graphene sheets. Thus, the techniques established in this study could also be applied to individual graphene layers.