One-step growth of graphene–carbon nanotube hybrid materials by chemical vapor deposition

Graphene–carbon nanotube (CNT) hybrid materials were synthesized by simple one-step chemical vapor deposition (CVD) using ethanol as precursor. On a copper foil decorated with silicon nanparticles (Si NPs), a graphene film grows uniformly on the substrate while CNTs sprout out from Si NPs to form a network on top. The density of CNTs can be controlled by the CVD growth temperature. As measured by scanning and transmission electron microscopy, the obtained CNTs exhibit bamboo-like multiple-wall structures. Electrical characterization shows that the graphene–CNT hybrids exhibit p-type field-effect characteristics and a significantly higher conductivity compared to a CVD grown pure graphene film.