Abstract

TiO2 nanorods in the brookite phase, with av. dimensions of 3-4 nm × 20-50 nm, were synthesized by a wet-chem. aminolysis route and used as precursors for thin films that were deposited by the matrix-assisted pulsed laser evapn. (MAPLE) technique. A nanorod soln. in toluene (0.016% TiO2) was frozen at the liq.-N temp. and irradiated with a KrF excimer laser at a fluence of 350 mJ/cm2 and repetition rate of 10 Hz. Single-crystal Si wafers, SiO2 slides, C-coated Cu grids and alumina interdigitated slabs were used as substrates to allow performing different characterizations. Films fabricated with 6000 laser pulses had an av. thickness of ∼150 nm, and a complete coverage of the selected substrate as achieved. High-resoln. scanning and TEM studies evidenced the formation of quite rough films incorporating individually distinguishable TiO2 nanorods and cryst. spherical nanoparticles with an av. diam. of ∼13 nm. Spectrophotometric anal. showed high transparency through the UV-visible spectral range. Promising resistive sensing responses to 1 ppm of NO2 mixed in dry air were obtained.

Details

Actions