Growth and Photocatalytic Properties of Gallium Oxide Films Using Chemical Bath Deposition

Gallium oxide (Ga 2O 3) thin films were fabricated on glass substrates using a combination of chemical bath deposition and post-annealing process. From the field-emission scanning electron microscopy and x-ray diffraction results, the GaOOH nanorods precursors with better crystallinity can be achieved under higher concentrations (≥0.05 M) of gallium nitrate (Ga(NO 3) 3). It was found that the GaOOH synthesized from lower Ga(NO 3) 3 concentration did not transform into α-Ga 2O 3 among the annealing temperatures used (400–600 °C). Under higher Ga(NO 3) 3 concentrations (≥0.05 M) with higher annealing temperatures (≥500 °C), the GaOOH can be transformed into the Ga 2O 3 film successfully. An α-Ga 2O 3 sample synthesized in a mixed solution of 0.075 M Ga(NO 3) 3 and 0.5 M hexamethylenetetramine exhibited optimum crystallinity after annealing at 500 °C, where the α-Ga 2O 3 nanostructure film showed the highest aspect ratio of 5.23. As a result, the photodegeneration efficiencies of the α-Ga 2O 3 film for the methylene blue aqueous solution can reach 90%. View Full-Tex