Microstructure and surface plasmon absorption of sol-gel-prepared Au nanoclusters in TiO2 thin films

Abstract

Using sol-gel processing and high temperature annealing, Au metal nanoclusters were prepared in TiO2 thin films. Au nanocrystal formation was confirmed by X-ray diffraction and its average particle size at the heat-treatment range of 500-900°C was measured as 16-29 nm in diameter by transmission electron microscopy. Compared with Au-SiO2, it has been observed that the peak of surface plasmon absorption is red-shifted to around 642 nm and its width is much broader, due to a strong interaction between the metal surface and the surrounding matrix.