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.