Localized surface plasmon resonance sensing properties of photocatalytically prepared Au/TiO2 films

Photocatalytic deposition of Au nanoparticles from a mixed aqueous solution of HAuCl4 and ethylene glycol onto TiO2 films (Au/TiO2 films) was carried out by using ultraviolet light irradiation at room temperature. In the optical absorption spectra of the Au/TiO2 film, the localized surface plasmon resonance (LSPR) peak of Au nanoparticles was observed at 534.5 nm. When the film was immersed in various kinds of solutions, such as alcohols, NaCl and D-glucose aqueous solutions, a linear relation was clearly observed between the LSPR peak wavelength and the refractive index of the solutions, in the range of 1.0003-1.4181. (C) 2008 Elsevier B.V. All rights reserved.