Preparation and photocatalytic activity of TiO2 films with Ni nanoparticles

Titania thin films were synthesized by sol–gel dip-coating method with metallic Ni nanoparticles synthesized separately from an organometallic precursor Ni(COD) 2 (COD = cycloocta-1,5-diene) in presence of 1,3-diaminopropane as a stabilizer. Titania was obtained from a titanium isopropoxide precursor solution in presence of acetic acid. A Ni/TiO 2 sol system was used to coat glass substrate spheres (6, 4 and 3 mm diameter sizes), and further heat treatment at 400 °C was carried out to promote the crystallization of titania. XRD analysis of the TiO 2 films revealed the crystallization of the anatase phase. Transmission Electron Microscopy (TEM) and High Resolution TEM studies of Ni nanoparticles before mixing with the TiO 2 solution revealed the formation of Ni nanostructures with an average size of 5–10 nm. High-angle annular dark-field images of the Ni/TiO 2 system revealed well-dispersed Ni nanoparticles supported on TiO 2 and confirmed by AFM analysis. The photocatalytic activity of the Ni/TiO 2 films was evaluated in hydrogen evolution from the decomposition of ethanol using a mercury lamp for UV light irradiation. Titania films in presence of Ni nanoparticles show higher efficiency in their photocatalytic properties in comparison with TiO 2 .