Field Emission Properties of Discrete Emitter Made of Graphene and Carbon Nanotubes

A discrete field emitter was fabricated by gluing carbon nanotubes(CNTs) onto tip-apex of pencil-lead with graphene slurry.The influence of the graphene-content on the field emission properties of the self-developed emitter was investigated.The preliminary results show that the graphene significantly improved the field emission property of the lab-made.Specifically, the de-bundled CNTs, being well dispersed, enclosed and tightly fixed to the tip-apex by graphene, formed the independent multiple emission sites.As the graphene content increased, the emission current density and field enhancement factor changed in an increase-decrease mode, the emission onset field decreased.The threshold current density from the emitter with a graphene content of 6 wt%,in the graphene aqueous slurry, was reached at the lowest electric field.In addition, the field emission behavior of the self-developed field emitters, with different graphene-contents, was found to be fairly stable.