Synthesis of β-Ga₂O₃ microstructures with efficient photocatalytic activity by annealing of GaSe single crystal

Graphical abstract: - Highlights: • Novel β-Ga₂O₃ microstructures were achieved through annealing of GaSe single crystal. • Micro-flowers and leaves were characterized through XRD, SEM and Raman spectroscopy. • A possible growth mechanism was proposed. • Photocatalytic performance was evaluated. - Abstract: The synthesis of new β-Ga₂O₃ microstructures was achieved through rapid annealing of GaSe single crystal at 850 °C in oxygen–ammonia co-flow for 30–120 min duration. The obtained micro-flowers and micro-leaves were carefully characterized through X-ray diffraction, scanning electron microscopy and Raman spectroscopy. SEM images demonstrated that the product consisted of flower-shaped microstructures, which as time elapsed evolved into leaves-like dendritic microstructures. These microstructures started off directly from oxidized single crystal. A possible growth mechanism was also proposed. Experimental results evidenced that synthesized microstructures exhibited good photocatalytic activity, better than commercial TiO₂ powder (Degussa P25)