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

Abstract

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 2 wt% of Ag loading on TiO₂, catalyst dosage of 400 mg L⁻¹, and calcination temperature of 300°C. Complete decolorization of the dye solution on Ag/TiO₂ was observed in 20 min of UV irradiation in the optimum conditions.

Keywords:

• Ag-loaded TiO₂
• heterogeneous photocatalysis
• microemulsion
• UV/TiO₂
• Acid Red 27

Acknowledgments

The authors would like to thank the financial support of Iranian Nanotechnology Society, the Islamic Azad University – North-Tehran and Tabriz branches and University of Tabriz.