Determination of the surface states of metallic clusters supported on alumina using microcalorimetry of CO adsorption

The adsorption of CO on alumina supported metal (Rh, Ru, Pt and Pd) catalys ts was studied by microcalorimetry and infrared spectroscopy. The correlati on of the results obtained from these two techniques provides information a bout the CO adsorbed species and the variations in the site energy distribu tion. Using these methods the nature and number of the surface sites on met al clusters, including aspects such as the presence of edge, corner or step atoms or the type of exposed crystalline planes, can be determined. Furthe rmore, the energetic distribution of surface sites has been shown to depend on the metal loading. (C) 2001 Elsevier Science B.V. All rights reserved.