Adsorption and desorption of CO on Ni decorated stepped Rh(553)

► CO adsorption on a Ni decorated stepped Rh(553) surface is investigated by TPD and RAIRS. ► The Ni decoration quenches the CO bridge position on the Rh steps. ► Ni decoration of the steps leads to 4 TPD peaks as compared to just one peak in clean Rh(553). ► Increasing the Ni coverage does not lead to a CO adsorption that is comparable to a stepped Ni surface.