Investigation On Alcohol Vapours/TiO2 Nanocrystal Thin Films Interaction By SPR Technique For Sensing Application

disponibile on line al link: http://dx.doi.org/10.1016/j.snb.2003.12.025 Surface plasmon resonance (SPR) was explored as optical transduction technique for monitoring the response of TiO2 thin films as sensing layers for alcohol vapours. Organic solutions of surfactant-capped TiO2 nanocrystals were prepared by means of a colloidal chemistry route, and used as precursors for depositing the sensing layer onto Au/glass substrates. The sensing properties of the active material were examined in relation to the morphological features of both as-deposited and thermally annealed films and to the presence of the organic passivating shell on the TiO2 nanocrystals surface. Untreated titania thin films exhibited a high and reproducible SPR response to alcohol vapours than the corresponding organic-free material. A beneficial role in the sensing process may therefore be attributed to the organic passivating layer on the nanocrystals surface