Single-crystal Bi 2 Ga 4 O 9 nanoplates with exposed {110} facets have been synthesized without any organic facet-controlling agents. The nanostructures and the formation process mechanism of the obtained Bi 2 Ga 4 O 9 nanoplates are investigated using XRD, TEM and SEM. UV–vis DRS and VB-XPS analyses demonstrate that the CB position of Bi 2 Ga 4 O 9 nanoplates is shifted up by 0.21 eV compared with that of Bi 2 Ga 4 O 9 particles. PL spectra and photoelectrochemical texts show that the separation efficiency of photogenerated electron-hole pairs of Bi 2 Ga 4 O 9 nanoplates is higher than that of Bi 2 Ga 4 O 9 particles. The enhanced photocatalytic activity of Bi 2 Ga 4 O 9 nanoplates is mainly ascribed to the exposed {110} facets. PL technique and radical trapping experiments demonstrate that h + , OH and O 2 − are responsible for the degradation of Acid Red 1 (AR1) over Bi 2 Ga 4 O 9 nanoplates.
