Acetylene assisted formation of GaN–carbon nanotubes heterojunction nanowires

Abstract

Acetylene assisted metal catalyzed synthetic approach was successfully used to fabricate nanowires with radial and axial heterojunctions of gallium nitride and carbon nanotubes. Encapsulated wurtzite GaN nanorods with diameters less than 12 nm were synthesized inside multiwall carbon nanotubes. Nanowires with repeated GaN@CNT–GaN segments can be formed through acetylene gas switching. High-resolution transmission electron microscopy, X-ray diffraction, Raman scattering and photoluminescence spectroscopy studies demonstrated that high quality wurtzite GaN nanostructures are synthesized. Room temperature photoluminescence spectra further confirm the good optical properties of synthesized GaN nanostructures. The size effect of GaN nanostructures encapsulated inside carbon nanotubes sheaths could possibly be responsible for the observed blue shift and sharp luminescence characteristic. The ability to rationally synthesize radial and axial gallium nitride–carbon nanotubes heterostructures should open up new opportunities for nanophotonics and nanoelectronics.