A facile route to synthesize β‐Ga₂O₃ nanoparticles from γ‐polymorph through a rapid microwave route and their optical properties

Due to the wide bandgap, monoclinic structure and thermodynamic stability, β‐polymorph form of Ga 2 O 3 nanomaterials is well‐received for various applications. However, as the γ‐Ga 2 O 3 is difficult to synthesize, less attention has been paid towards it and its conversion to β‐polymorph. This paper reports the single‐step synthesis of γ‐Ga 2 O 3 using a microwave‐assisted procedure. In this regard, γ‐Ga 2 O 3 powders are synthesized in minutes using benzyl alcohol as the solvent using gallium acetylacetone as the precursor. The XRD of the as‐prepared powders indicates the formation of the γ‐Ga 2 O 3 phase, the very broad peaks indicative of the small crystallite size as confirmed by TEM. The γ‐Ga 2 O 3 powders were annealed at different temperatures and the complete phase conversion of γ‐Ga 2 O 3 phase to β‐Ga 2 O 3 phase happens at 700 °C. The TEM analysis shows the crystallite size to be ≈10 nm for the annealed β‐Ga 2 O 3 phase. The as‐prepared nanopowders show very weak luminescence under excitation and in contrast, a blue‐green emission is observed in case of annealed powders. This confirms the presented strategy as having the potential to use β‐Ga 2 O 3 nanopowders for different optoelectronic applications.