Influence of coating and annealing on the luminescence of Ga2O3 nanowires

초록

Ga2O3/CdO coaxial nanowires were synthesized by a two step process comprising the thermal evaporation of GaN powders and the sputter-deposition of CdO. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis results indicated that the cores and the shells of the annealed coaxial nanowires were single crystal monoclinic Ga2O3 and crystal face-centered cubic CdO, respectively. The major photoluminescence emission was slightly decreased in intensity by CdO coating, but it was significantly increased by subsequent thermal annealing in a reducing atmosphere. The major emission peak was also shifted from ~ 500 to ~ 510 nm by annealing in a reducing atmosphere, which is attributed to the increases in the Cd interstitial and O vacancy concentrations in the cores.