Characterization and photocatalytic activity of enhanced copper-silica-loaded titania prepared via hydrothermal method

Abstract

TiO 2 nanopowder, loaded with SiO 2 and Cu-SiO 2, was prepared under both acidic and basic environments via the hydrothermal method. The morphology and structure of TiO 2 were studied by XRD, TEM, and FT-IR. The photocatalytic activity of samples was studied by monitoring the degradation of methyl orange, using a UV-visible spectrophotometer. The effect of Ti/Si ratio, pH, and Cu 2+ addition on the formation of TiO 2 and its photocatalytic activity was investigated in detail. The results show that a large surface area and a high surface acidity were important factors to achieve good TiO 2 performance. The presence of Ti-O-Si bonding enhanced surface acidity, which improved its ability to adsorb more hydroxyl radicals and increased its surface area. The addition of 0.1mol concentration of Cu 2+ and 25mol SiO 2 in TiO 2 induced the formation of new states close to the conduction band, which narrowed the band gap energy and enhanced the photodegradation efficiency. Copyright © 2011 Ramarao Poliah and Srimala Sreekantan.