Properties of TiO2/Au nanocomposite produced by pulsed laser irradiation of mixture of individual colloids

Abstract

TiO2/Au nanocomposite was produced by irradiating the mixture of Au and TiO2 nanoparticle suspensions with the second harmonic beam of Nd:YAG pulsed laser. TiO2 and Au nanoparticles were produced by laser ablation method separately. Titanium dioxide and gold nanoparticles were prepared by ablation of a high purity titanium and gold plates in deionized water, respectively. The fundamental wavelength of a Nd:YAG laser operating at 1064 nm with pulse width of 7 ns and 10 Hz repetition rate was employed to produce nanoparticles. Targets was placed on the bottom of water contain. The synthesized Au and TiO2 colloidal solutions were mixed in equal volumetric ratio and irradiated with the 532 nm laser. The laser spot size was 6 mm on the solution surface, and the laser fluence during the post-irradiation was at 2 J/cm2. Irradiation was done using 5000 pulses at 10 Hz repetition rate and 7 ns pulse width. Results show that the absorption spectrum of nanocomposite is similar to TiO2 spectrum with a surface plasmonic absorption peak at about 530 nm. Both lattice structure of TiO2 and Au nanoparticles appears in the lattice structure of nanocomposite.