Photodegradation of an azo dye by silver-doped nano-particulate titanium dioxide

The synthesis of silver doped nano-particulate titanium dioxide (Ag/TiO2) using a microemulsion method and an investigation of its photocatalytic activity for the degradation of Acid Red 27 in distilled water under UV-irradiation is reported. The prepared Ag/TiO2 is characterized using transmission electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy. The size of the Ag nanoparticles is around 5-15 nm, with almost uniform distribution on the TiO2 particles. The efficiency of the photocatalytic process is evaluated to establish the optimum conditions, found to be at 2wt% of Ag loading on TiO2, catalyst dosage of 400 mg L-1, and calcination temperature of 300 degrees C. Complete decolorization of the dye solution on Ag/TiO2 was observed in 20 min of UV irradiation in the optimum conditions.