Ga2O3 nanowires grown on GaN-Ga2O3 core-shell nanoparticles using a new method: Structure, morphology, and composition

Ga₂O₃ nanowires grown on GaN-Ga₂O₃ core-shell nanoparticles were prepared through heat-treating GaN powder method which comprises a pre-nitridation process in the flow of N₂ gas and a post-oxidation process in the air at 1200 °C. XRD and EDS patterns indicated that the heat-treated GaN powders were a powder mixture of GaN and Ga₂O₃. SEM, TEM, HRTEM and SAED images revealed that some nanowires that grow out from the edge of the GaN-Ga₂O₃ core-shell nanostructures with atomically smooth interfaces were monoclinic Ga₂O₃. Large blue-shifts in vibration frequency of Ga-N bonds observed in the FTIR spectrum could be contributed to size confinement effect and internal strains in GaN nanoparticles.