An all-graphene based transparent and flexible field emission device

All-graphene based cathode and anode structures were fabricated and their application as a flexible and transparent field emission device is presented. The graphene film was grown on a Cu foil by thermal chemical vapor deposition and later transferred to a polymer substrate through a hot press lamination technique. Multiwall carbon nanotubes (MWCNTs) were spin-coated onto a graphene film on a transparent, flexible substrate to form the cathode of the field emission device. A green-phosphor coated graphene-PET film was used as the anode. The device showed good transparency and flexibility as well as giving an appreciable emission current. The simple processing techniques used can easily be upgraded to a larger scale and be tailored for any transparent and flexible substrate. The device offers exciting applications of carbon nanostructures in foldable electronics.