(Invited) Flexible 3-Dimensional Graphene Foam-Based NO2 Gas Sensors

Graphene has attracted much attention due to its great optical and electronic properties. Since indium-tin-oxide which is common transparent-conductive-layer in GaN-based light-emitting diodes (LEDs) has reached its limitation, many researchers have focused on the applications of graphene as transparent-conductive-layer in optoelectronic devices, for instances LEDs and solar-cells. Especially, the exceptional transmittance in UV (ultra-violet) and IR (infra-red) spectral ranges opens a new possibility for the graphene to be integrated with UV-LEDs. However, the high sheet resistance of the graphene is still an issue in its implementations. The methods to improve the sheet resistance and the stability by a chemical doping method will be discussed.