TiO2 nanoparticle thin film deposition by matrix assisted pulsed laser evaporation for sensing applications

The MAPLE technique has been used for the deposition of nanostructured titania (TiO2) nanoparticles thin films to be used for gas sensors applications. An aqueous solution of TiO2 nanoparticles, synthesised by a novel chemical route, was frozen at liquid nitrogen temperature and irradiated with a pulsed ArF excimer laser in a vacuum chamber. A uniform distribution of TiO2 nanoparticles with an average size of about 10 nm was deposited on Si and interdigitated Al2O3 substrates as demonstrated by high resolution scanning electron microscopy-field emission gun inspection (SEM-FEG). Energy dispersive X-ray (EDX) analysis revealed the presence of only the titanium and oxygen signals and FTIR (Fourier transform infra-red) revealed the TiO2 characteristic composition and bond. A comparison with a spin coated thin film obtained from the same solution of TiO2 nanoparticles is reported. The sensing properties of the films deposited on interdigitated substrates were investigated, too.