Indium-assisted synthesis on GaN nanotubes

Abstract

Gallium nitride (GaN) nanotubes in a high yield were synthesized by a simple indium-assisted thermal evaporation method in the presence of ${\mathrm{NH}}_3$ gas flowing. A vapor–liquid–solid process was proposed for formation of the GaN nanotubes. The synthesized GaN nanotubes were amorphous and partially filled with indium, several micrometers in length, 40–50 nm in outer diameter, and 7 nm for the tube wall thickness. The representative photoluminescence spectrum at room temperature exhibits a great shift from the band gap of 3.40 eV (365 nm) of bulk GaN to high energy of 3.63 eV (342 nm). The synthetic route for the GaN nanotubes is simple and effective, and could provide great opportunities for both fundamental and technological applications.