Synthesis and Characterization of Gallium Oxide Nanostructures via a Soft-Chemistry Route

Nano- to microsized gallium oxide was prepared with and without surfactant via a hydrothermal route at low temperature through different synthesis procedures. Rodlike GaOOH crystals with average length of ∼2.5 μm and width of 1.5 μm were prepared when the initial molar ratio of Ga to OH was 1:3. β-Ga2O3 materials were derived from GaOOH by calcination at 900 °C, and the initial morphology was retained. γ-Ga2O3 nanotubes up to 65 nm in length, with internal and external diameters of around 0.8 and 3 nm, were achieved directly in solution with and without surfactant under hydrothermal treatment condition at 100 °C when the initial molar ratio of Ga to OH was 1:5. The combination of X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption, small area electron diffraction (SAED), and energy dispersive X-ray analysis (EDX) were employed to characterize the resulting nano- to microsized structures. Cationic and nonionic surfactants were used in this study. Detailed results are presented.