H2 adsorption and dissociation on PdO(101) films supported on rutile TiO2 (110) facet: elucidating the support effect by DFT calculations.

To explore metal oxide-support interactions and their effect, H2 adsorption and dissociation on PdO(101)/TiO2(110) films with different film thicknesses, in comparison with that on pure PdO(101) surface without TiO2(110) support, were studied by density functional theory calculation. A monolayer PdO(101) film supported on TiO2 facet shows different properties to a pure PdO(101) surface. On the monolayer PdO(101)/TiO2(110) film, TiO2 support leads to stronger molecular adsorption of H2 on coordinatively unsaturated Pd top sites than that on a pure PdO surface. H2 dissociation with the formation of OH was preferred thermodynamically but slightly unfavorable kinetically on the monolayer PdO film due to the TiO2 support effect. Graphical abstract On the monolayer PdO(101)/TiO2(110) film, the TiO2 support effect leads to stronger H2 molecular adsorption on coordinatively unsaturated Pd top sites than on pure PdO surface. H2 dissociation with the formation of OH is preferred thermodynamically but slightly unfavorable kinetically on the film due to the TiO2 support effect.