Surface-Enhanced IR Absorption (SEIRA) of CO Adsorbed on Small Pt Particles Deposited on an Island Au Film

CO adsorbed on Pt particles deposited on an island Au film exhibited strong IR adsorption. Since Au is not able to adsorb CO, this is attributable to surface-enhanced IR absorption (SEIRA) caused by the Au film. When Pt deposits were extremely small, C-O stretching band appeared at frequencies much lower than those observed for supported Pt catalysts, indicating that the Pt deposit was so small that adsorbed CO was isolated each other without a dipole-dipole interaction.