Effect of Pd on the interaction of formic acid with TiO2(110)

The effect of coadsorbed Pd on the adsorption of HCOOH on TiO2(110) at room temperature has been investigated using HREELS. At Pd coverages below 12 ML, formate is evidenced that is probably bonded to Ti sites on bare areas of the substrate. Additional CO species are identified corresponding to CO bound to Pd clusters as well as HCO and/or CO bound to sites at the perimeter of the clusters. There is evidence of Pd encapsulation by TiO2−x after annealing the Pd overlayer to 800 K.