Synthesis and photocatalytic activity of ultrafine Ag3PO4 nanoparticles on oxygen vacated TiO2

Despite high activity for photocatalytic degradation of organic dyes from water, nanoscale Ag 3 PO 4 photocatalyst particles are difficult to synthesize. As reported in literature, Ag 3 PO 4 particle sizes for photocatalytic degradation of water pollutants are normally larger than 100   nm. This research reports a facile and reproducible method for the synthesis of the ultrafine and uniform Ag 3 PO 4 nanoparticles loaded on the oxygen vacated TiO 2 (TiO 2 -OV) with average particle size as small as 2.6   nm. All obtained Ag 3 PO 4 particles can be completely loaded onto TiO 2 -OV support to form Ag 3 PO 4 /TiO 2 -OV composite photocatalysts. The prepared Ag 3 PO 4 /TiO 2 -OV photocatalyst exhibits much higher visible light photocatalytic activity than those of pure Ag 3 PO 4 or Ag 3 PO 4 /TiO 2 photocatalysts for the degradation of rhodamine b (Rh B) and phenol in water. After depositing thin layers of AgI on Ag 3 PO 4 ultrafine Ag 3 PO 4 nanoparticles, the new AgI-Ag 3 PO 4 /TiO 2 -OV composite photocatalysts not only show much higher photocatalytic activity, but they are also more stable than pure Ag 3 PO 4 catalyst. This new synthesis method will provide guidelines for the preparation of ultrafine nanoparticles and highly active photocatalysts for treatment of water pollution or production of hydrogen from water splitting/reducing.