Low-temperature sol-gel synthesis photochromic Cu/TiO2 films

Synthesis of photochromic, highly photoactive Cu@TiO2 films by low-temperature sol-gel route has been reported. The photoelectric properties of nanostructured non-calcined composite film are higher than that in individual compounds. Synthesized films are characterized by AFM, UV-vis absorption spectra and X-ray diffraction. The functional properties are estimated by photopolarization measurement. Titania films were soaked with a copper salt solution and chemical reduction treatments are performed using NaBH4. We used P123 for protection metal surface and decreasing agglomeration activity. Also, the utilization of a mesoporous titania substrate allows to control the nanoparticle size and the interparticle distance. UV-vis absorption spectra experiments provide the evidence that UV illumination induces a strong accumulation of copper nanoparticles in the subsurface of the layer. (C) 2011 Elsevier B. V. All rights reserved.