Preparation and photocatalytic activity of ZnGa2O4-β-Ga2O3 thin films

ZnGa2O4 and ZnGa2O4-beta-Ga2O3 thin films were prepared via aerosol-assisted chemical vapor deposition (AACVD) using various ratios of the Zn and Ga precursors, resulting in the formation of amorphous ZnGa2O4 and Ga2O3. The formation of crystalline zinc gallate and heterostructure zinc gallate thin films was achieved by annealing the resulting films at high temperatures under air. The ZnGa2O4-beta-Ga2O3 thin films showed enhanced photocatalytic activity compared with ZnGa2O4. The photocatalytic enhancement of the ZnGa2O4-beta-Ga2O3 is explained by the formation of type-II band alignment at the interfaces between ZnGa2O4 and Ga2O3, resulting in enhanced photoinduced charge separation in the material.