Synthesis of a three dimensional structure of vertically aligned carbon nanotubes and graphene from a single solid carbon source

Abstract

Here, we demonstrate the synthesis of a three dimensional (3D) structure of vertically aligned carbon nanotubes (VACNTs) and graphene from a single solid carbon source. Graphene growth on Cu foil is achieved using solid camphor as the carbon source, whereas the VACNTs are obtained by adding a small amount of ferrocene in the camphor feedstock with minimum contamination from the iron catalyst. Highly dense VACNTs are grown on a transferred graphene film to fabricate the hybrid structure. Raman spectroscopy, optical and scanning electron microcopy studies confirm out of plane growth of the carbon nanotubes (CNTs) from the graphene film. Current-voltage (I-V) measurements are performed to investigate the in plane and out of plane electrical characteristics of the 3D structure. Contact resistance of the VACNTs-graphene is explored taking into account the other resistive contacts in the 3D material system. Achieving a seamless contact of VACNTs-graphene film is significant for low contact resistance and thereby practical device application.