Transparent electrodes made of graphene by a solution process have the potential to be applied in electronics at low cost. However, when a thin film is fabricated with microscale graphene sheets, unconnected boundaries can occur between flakes, which results in high sheet resistances.

To enhance the conductivity of the film, the group uses carbon nanotubes (CNTs) to bridge the gaps, as shown in the conceptual diagram above. High-performance conductive films having a resistance of 181 Ωsq–1 and a transmittance of 82.2% were fabricated after chemical treatment and doping.

The fabrication of flexible optical electronic devices such as OLEDs and solar cells is ongoing in Heeyeop Chae's group. "We are keen to develop this novel electrode material for organic and flexible electronic devices and further results will be published soon," Heeyeop Chae told

More details can be found in the journal Nanotechnology.