Heats of adsorption of the linear CO species on Pt/Al2O3 using infrared spectroscopy: impact of the Pt dispersion

In previous studies, it has been shown that the heats of adsorption at several coverages of each adsorbed CO species (linear, bridged, and threefold coordinated) on a 2.9% Pt/Al2O3 catalyst can be obtained from the change in the IR band area of each adsorbed CO species with the adsorption temperature Ta (in the 300–800 K range) at a constant CO partial pressure Pa. In the present study, this procedure is used to reveal the eventual impact of the Pt dispersion (range 0.44–0.75) on the heats of adsorption of the linear CO species adsorbed on several Pt/Al2O3 catalysts. It is shown that the Pt dispersion has no strong impact on this parameter at several coverage values.