Electronic structure of acetonitrile adsorbed on the anatase TiO2 (1 0 1) surface

We have investigated detailed electronic states of acetonitrile (MeCN) molecule adsorption on the anatase (1 0 1) TiO2 surface by using the density functional theory with a hybrid exchange correlation functional for deeper understanding of dye-sensitized solar cells interfaces. Our analysis indicates that the 7a1 orbital of MeCN hybridizes with the non-bonding orbitals of threefold coordinated oxygen (O3C) on the surface, not directly to the fivefold coordinated Ti (Ti5C). This mechanism accounts for the stable adsorption geometry of MeCN and the coverage of MeCN molecules on the surface.