The growth pattern and electronic structures of Cun(n=1-14) clusters on rutile TiO2(110) surface

The growth pattern and electronic properties of Cu-n (n = 1-14) clusters supported on rutile TiO2(1 1 0) surface have been studied by using the density functional theory method. The calculation results showed that the supported Cu-n (n = 3-5,7) clusters prefer planar or quasi-planar structures, while Cu-n (n = 6,8-14) clusters prefer three-dimensional structures. The stabilities of Cu-n/TiO2 show an odd-even oscillation behavior with the increasing n, except n = 2 and 7. For the supported Cu-n, the clusters with odd n are more stable than the adjacent clusters. The charge transfer from Cu-n clusters to TiO2 surface was observed. The electron densities of Cu atoms adjacent to O atoms of the surface are obviously reduced. Electronic structure analysis indicated: (1) Electrons are transferred from Cu-n clusters to the valence band of TiO2 surface. (2) The states from Cu-n clusters appear in the energy gap of the TiO2 surface and the energy gaps between the occupied states from Cu-n clusters and the unoccupied states from TiO2 surface decrease with the increasing n. Our calculations showed that the visible light irradiation can further enhance the charge transfer from the Cu-n clusters (with diameter smaller than 0.6 nm) to TiO2 surface and facilitate the reduction reactions (such as CO2 reduction reaction) on the TiO2 surface.

Automated summary

The growth pattern and electronic properties of Cu-n clusters supported on rutile TiO2(1 1 0) surface were studied using density functional theory. Results showed stability patterns of the clusters and charge transfer phenomena between Cu-n clusters and TiO2 surface.