Encapsulated Pd Nanocrystals Supported by Nanoline-Structured SrTiO3(001)

Palladium nanocrystals were grown on a nanostructured SrTiO3(001) surface and annealed in ultrahigh vacuum at 620 °C. This leads to the so-called strong metal−support interaction (SMSI) state, characterized by encapsulation of the metal clusters with an oxide layer. Scanning tunneling microscopy (STM) of the oxide adlayer on the Pd(111) cluster surface reveals two superstructures with different lattice parameters and crystallographic rotations. Interpretation of the STM images is most readily achieved via noncommensurate TiO x surface layers which result in two distinct Moiré patterns.