Highly dispersed Au nanoparticles incorporated mesoporous TiO₂ thin films with ultrahigh Au content

Highly dispersed gold nanoparticles (NPs) incorporated mesoporous titania thin films with ultrahigh Au content (53.3 wt%) were synthesized by a deposition-precipitation method using urea as precipitator, which showed high off-resonant third-order optical nonlinear susceptibility (χ⁽³⁾ = 2.69 × 10^-8 esu) measured by the Z-scan technique at 1064 nm. The enhanced χ⁽³⁾ value of the materials was attributed to the homogeneous dispersion and the ultrahigh concentration of the gold NPs, and the high linear refractive index of the titania matrix.