Microstructure of precipitated Au nanoclusters in TiO ₂

Gold (Au) nanoclusters embedded in TiO ₂ single crystal were prepared by 2 MeV ion implantation and subsequent annealing at 1275 K. Scanning Transmission electron microscopy-high angle annular dark-field (STEM-HAADF) image revealed that Au atoms were in substitutional Ti atomic column in the TiO ₂ lattice prior to the nucleation of the Au lattice. The embedded Au clusters were faceted along Au{112} and Au{111} or Au{220} and Au{002} planes and possessed (111) twins. The precipitated Au nanoclusters were found to exhibit unique orientation relationships with respect to the TiO ₂ matrix. These orientation relationships were shown to be the preferred orientation relationships between Au and TiO ₂.