Mesoporous mixed-phase Ga2O3: Green synthesis and enhanced photocatalytic activity

•Mixed-phase Ga2O3 was synthesized by a facile and green method.•Mixed-phase Ga2O3 exhibited good photocatalytic activity and stability.•The reactive species in the photocatalytic process were investigated.

Mesoporous mixed-phase Ga2O3 was synthesized by calcining the GaOOH precursor. The composition, crystal phase and microstructures of Ga2O3 were characterized in detail. The phase composition of the as-prepared Ga2O3 depended on the calcination temperature and the mixed-phase Ga2O3 was obtained at 600–700 °C. As compared to the pure-phase α-Ga2O3 and β-Ga2O3, the mixed-phase Ga2O3 exhibited an enhanced photocatalytic property for the degradation of metronidazole solution. The heterojunction in the mixed-phase Ga2O3 was beneficial to the separation of photogenerated electrons and holes. Moreover, the mixed-phase Ga2O3 possessed mesopore structure, which increased more reaction sites and was in favor of the contact of metronidazole molecules with reaction sites. The recycling experiments show that the mixed-phase Ga2O3 has good stability and can be separated easily from the reaction system.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide