Sonochemical deposition of silver-TiO2 nanocomposites onto foamed waste-glass: Evaluation of Eosin Y decomposition under sunlight irradiation

TiO2 and Ag-TiO2 nanocomposites have been deposited on commercial foamed waste-glass strips (FWGS) by the sonochemical technique. The coated FWGS were characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray spectroscopy (EDS). The addition of polyvinyl alcohol as surfactant to the sonochemical deposition process enhances the nanocomposite deposition, resulting in the formation of TiO2 composites which are compact, uniform and adherent to FWGS. SEM images show that the oxides which were deposited consist of interconnected aggregates quasi-spheres similar to 25 nm in width. Energy dispersive spectroscopy data revealed oxides of TiO2 formed onto the porous aluminosilicate. Surface morphology studies reveal randomly oriented aggregates with a raising structure around the pores with an average similar to 5 mu m of diameter. The coated strips were evaluated for photoxidation of Eosin Y dye under sunlight. Experiments to evaluate the photocatalytic activity of supported TiO2 were performed in common glass bottles under solar irradiation. Silver-titania-coated strips had the optimal performance, achieving 50% of mineralization and total Eosin Y solar discoloration. (C) 2010 Elsevier B. V. All rights reserved.