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/mu m) and threshold field (1.51 V/mu m), large field enhancement factor (similar to 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. (C) 2012 Elsevier Ltd. All rights reserved.