Fabrication and photoluminescence of GaN nanorods by ammoniating Ga2O3Ga2O3 films deposited on Co-coated Si(1 1 1) substrates

GaN nanorods were synthesized in mass by ammoniating Ga2O3Ga2O3 films sputtered on Si(1 1 1) substrates using cobalt as a catalyst. X-ray diffraction, scanning electron microscope, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy and photoluminescence were used to characterize the products. The results show the as-synthesized samples are of single-crystalline hexagonal wurtzite structure with the space group of P63mcP63mc. The nanorods are straight and have a smooth surface with diameters around 200 nm and lengths up to tens of microns. The catalytic growth mechanism of GaN nanorods was also discussed.