Enhanced Photocatalytic Activity in β‐Ga2O3 Nanobelts

β‐Ga 2 O 3 nanobelts have been synthesized by a vapor transport process under different ambient oxygen. Their structural and optical properties were characterized by field‐emission scanning electron microscopy, X‐ray diffraction, photoluminescence (PL), and absorbance measurements. Structural characterization revealed that the as‐synthesized samples consist of monoclinic β‐Ga 2 O 3 nanobelts with comparable surface area. Samples prepared under high oxygen ambient possessed large numbers of gallium‐associated defects confirmed by PL and absorbance measurements. The photocatalytic activity of β‐Ga 2 O 3 nanobelts was evaluated by the degradation of organic dyes (rhodamine B and methyl blue) under ultraviolet light illumination. The results demonstrated that β‐Ga 2 O 3 nanobelts exhibited superior photocatalytic activity and stability as compared with commercial β‐Ga 2 O 3 powder. The photocatalytic activity of β‐Ga 2 O 3 nanobelts was greatly enhanced and attributed to the large numbers of acceptor states associated with gallium defects. The origin of enhanced photocatalytic activity of β‐Ga 2 O 3 nanobelts was discussed.