Excellent field emission characteristics from few-layer graphene–carbon nanotube hybrids synthesized using radio frequency hydrogen plasma sputtering deposition

The growth of few-layer graphene (FLG) on carbon nanotubes (CNTs) was realized by using radio frequency hydrogen plasma sputtering deposition. A defect nucleation mechanism and a two dimensional growth model of the FLG were proposed, and field emission characteristics of these FLG–CNT hybrids were studied. They show excellent field emission properties, with a low turn-on electric field (0.98 V/μm) and threshold field (1.51 V/μm), large field enhancement factor (∼3980) and good stability behavior, which are much better than those of the as-grown CNT arrays. The sharp edges and the low work function of the hybrids are believed to be responsible for the improved field emission properties.