Synthesis of β-Ga₂O₃ nanowire from elemental Ga metal and its photoluminescence study

Gallium oxide (Ga₂O₃) one-dimensional (ID) nanostructure was fabricated through a simple physical evaporation of elemental gallium in argon atmosphere using gold-sputtered silicon as the substrate. The shape of the ID structure was controlled by the thickness of the sputtered gold layer. Monoclinic Ga₂O₃ structure was identified by X-ray diffraction XRD and electron diffraction patterns. High-resolution transmission electron microscopy revealed that these nanowires were single crystalline in nature. Energy dispersive X-ray indicated stoichiometric composition of the nanomaterial. Photoluminescence measurement under excitation at 250 nm showed that these nanowires had three emission peaks at 373, 410 and 475 nm, which may be attributed to the defects such as oxygen vacancy (V_O) and gallium-oxygen vacancy pair (V_O,V_Ga).