Photoluminescence of nanocrystalline titanium dioxide films loaded with silver nanoparticles

We report on a systematic study of the photoluminescence properties of nanocrystalline titanium dioxide films loaded with silver nanoparticles under various ambient conditions: in the temperature interval of 10 to 300 K, under different values of ambient air pressure (5 to 10(5) Pa), and under visible light irradiation that causes the photochromic transformation of the film. Our results enable us to follow the electron transfer from titanium dioxide into silver nanoparticles and to observe the oxidation of silver nanoparticles during the photochromic transformation. We propose a microscopic model explaining the behavior of extinction and photoluminescence of the Ag-TiO2 film under different values of ambient air pressure. (C) 2011 American Institute of Physics. [doi:10.1063/1.3573486]