Nanoclusters of TiO2 wetted with gold

We combined scanning tunneling microscopy and density functional theory to establish the structure–functionality relationship for nanometer-sized defects on TiO2(1 1 0). Three-angstrom high topographically distinct dots are ascribed to stoichiometric TiO2 nanoclusters with low coordination numbers. The under-coordinated O atoms of the nanocluster, with surface O atoms, provide exceptionally strong binding sites for Au nanoparticles. Our atomistic model elucidates a number of characteristics salient to low temperature CO oxidation by Au nanoparticles.