Properties of small metal particles

Characterization of Au-Rh/TiO2 catalysts by CO adsorption; XPS, FTIR and TPD experiments

“…It turned out in the very early stage of the studies that the models built up for the non-supported bimetallic systems (such as rigid band model [13]), formation of alloy [14][15][16][17], surface enrichment in the component with lower heat of sublimation [18], "cherry model" [19], coherent potential approximation [16,17], ensemble and ligand effect [18][19][20][21][22] and electron transfer [23,24]) cannot be simply transformed to the supported bimetallic catalysts. UPS studies [25,26] revealed that metal crystallites having more than 150 atoms behave like a bulk metal. At lower particle sizes (ca.…”

Metal Nanoclusters: Electronic Aspects and Physico-Chemical Characterization

“…The onset of spectral modulations has been reported for both gold and silver clusters evaporated onto carbon [33]. Changes in the final state that accompany changes in photon excitation energy should give changes in the transition matrix element and lead to spectral modulations if the cluster is large enough to have a bulk-like periodic structure.…”

“…In the eighties Baetzold and his school [27][28][29][30][31][32][33] carried out fundamental investigations on small clusters. The photoemission spectra of Ag and Cu clusters, as a function of their coverage on carbon support, show considerable changes in the spectra as size (or coverage) increases [34].…”

“…Ionization potential of metal clusters is one of the factors affected by cluster size [33]. This study represents the most extensive effort so far to determine the size dependence of IP.…”

“…This effect is another convenient measure of the progression to bulk behavior [33]. This effect is another convenient measure of the progression to bulk behavior [33].…”