Preparation of nano-sized silver vanadates: characterization and photocatalytic activity

Nanocrystalline mesoporous silver vanadate oxides were successfully prepared using a ball milling process. Under the optimal conditions, the silver vanadate oxides sample milled at 12 h (SVO12) powder has larger Brunauer–Emmett–Teller surface area (5.81 m 2 /g as opposed to 0.02 m 2 /g) than the starting silver vanadate oxides. The photocatalytic activity of the milled silver vanadate oxides was higher than that of unmilled silver vanadate oxides. The SVO12 exhibits the best photocatalytic activity; it has a reaction rate constant ( k app ) of 0.11 min −1 , much higher than that of unmilled silver vanadate oxides ( k app = 0.02 min −1 ). The photoactivity enhancement is due to increasing photoabsorption efficiency and improving reaction/diffusion of molecules through the mesoporous structure.