Formation and Characterization of Au/TiO{sub 2} NanoComposite by Laser Irradiation

Nanosized noble metal particles and dielectric matrix composite materials have attracted extensive attention due to their large third-order nonlinear susceptibility and ultrafast response properties, and have great potential for applications in optical devices. In this study, composite Au/TiO{sub 2} nanoparticles were synthesized by laser irradiation. Characterization of the composite particles by means of UV-Vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), and atomic force microscopy (AFM) was carried out. We have successfully produced composite Au/TiO{sub 2} nanoparticles by laser ablation of metal gold plate in TiO{sub 2} sol. The red shift of 30 nm in the surface plasmon band of Au is found due to the refractive index of TiO{sub 2}. The surrounding TiO{sub 2} matrix is amorphous, but upon heat treatment becomes a crystalline oxide. Various morphologies of particles are visible, including circular, hexagonal and triangular projection; circular and thus spherical particles being the most common, which were confirm by the TEM images. A large size distribution of particles is visible in TEM images; the average grain size was measured 35 nm, which was confirmed by X-ray diffraction studies.