Field electron emission response of reduced graphene oxide based hierarchical structures

Field emission is a process of electron emission from the surface of a material through quantum tunneling in the presence of an applied electric field. Emission of electrons from a material becomes easy if material is synthesized in the form of nanoscale sharp tips. In the present work, we synthesized one dimensional nanostructures (1-D) such as copper oxide (CuO) nanorods and carbon nanotubes (CNTs) by wet chemical and chemical vapor deposition (CVD) methods, respectively. As the electron field emission (FE) from the flat surface of graphene is challenging, the reduced graphene oxide (RGO) was coated on CuO nanorods and CNTs to prepare RGO based hybrids for field emission. Basic idea to support RGO on 1-D nanostructures was to produce high density sharp protrusions/ridges in RGO sheets. A comparison between the FE characteristics of 1-D nanostructures and RGO based hybrid emitters was performed.