The Influence of Metal Cluster Size on Adsorption Energies: CO Adsorbed on Au Clusters Supported on TiO_2

摘要

Infrared reflection absorption spectroscopy (IRAS) has been used to study CO adsorption on Au clusters ranging in size from 1.8 to 3.1 nm, supported on TiO_2. The adsorbed CO vibrational frequency blue-shifts slightly (approximately 4 cm~(-1)) compared to that adsorbed on bulk Au, whereas the heats of adsorption (-ΔH_(ads)) increase sharply with decreasing cluster size, from 12.5 to 18.3 kcal/mol.