Synthesis and structural properties of beta-gallium oxide particles from gallium nitride powder

Beta-gallium oxide (β-Ga2O3) powders have been synthesized through simple thermal annealing gallium nitride (GaN) powders in the opening air at 900 °C. The course of β-Ga2O3's formation and its structural properties were studied by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photo-electron spectroscopy (XPS). The observations revealed that Ga2O3 on the surface of GaN particles has been formed below 500 °C, the rate of Ga2O3's formation under air is slow in the temperature range from 500 to 800 °C and is fast in the temperature range of 800–900 °C. The as-obtained products at 900 °C are pure, single-crystalline monoclinic Ga2O3 particles, and the size of β-Ga2O3 is about 50–300 nm.