Influence of oxygen pressure on the structure and photoluminescence of β-Ga2O3 nano-material prepared by thermal evaporation

We have prepared the gallium oxide (beta-Ga2O3) nanomaterials from gallium and oxygen by thermal evaporation in the argon atmosphere and researched their photoluminescence (PL). X-ray diffraction (XRD) revealed that the synthesized products are monoclinic gallium oxide, and its morphology as observed by the scanning electron microscope ( SEM) revealed that Ga2O3 nanobelts with breadth less than 100 nm and length of several micrometers are synthesized under low oxygen pressure, while nanoparticles are synthesized under high oxygen pressure. Room-temperature photoluminescence under excitation of 325 nm shows that the beta-Ga2O3 nanostructures have stable emission at 516 nm, which may be related to the defects such as the oxygen vacancies and the gallium-oxygen vacancy pairs.