Adsorption of CO and C2H4 on Rh-loaded thin-film dysprosium oxide

A dysprosium oxide thin film was deposited on Ru(0 0 0 1) by vapor depositing Dy in 2 × 10−7 torr O2 while the Ru was at 700 K. The film was ca. 5 nm thick and produced a p(1.4 × 1.4) LEED pattern relative to the Ru(0 0 0 1) substrate. The adsorption and reaction of CO and C2H4 adsorbed on Rh supported on the Dy2O3 film were studied by TPD and SXPS. The CO initially reacted with loosely bound oxygen in the substrate to produce CO2. After the loosely bound oxygen was removed, the CO adsorbed non-dissociatively in a manner similar to what is seen on Rh(1 1 1). C2H4 adsorbed on the Rh particles and underwent progressive dehydrogenation to produce H2 during TPD. The C from the C2H4 reacted with the O in Dy2O3 to produce CO. CO dissociation on the Rh particles could be promoted by treating the Dy2O3 with C2H4 before CO exposure.