Adsorption of CO on Pd/Al2O3/Ta(110) model catalysts
نویسندگان
چکیده
The adsorption of CO on Pd/Al2O3/Ta~110! model catalysts was studied using infrared reflection adsorption spectroscopy ~IRAS! for two different Pd coverages, corresponding to 25–30 and 60–70 Å average particle sizes. Striking similarities between the IRAS data for the larger particles and Pd single crystals indicate that the particles are comprised predominantly of ^111& and ^100& facets. The isosteric heat of adsorption of CO extrapolated to zero coverage was determined to be 38.9 kcal/mol on the 60–70 Å particles. IRAS and Auger results provide evidence of CO dissociation on the smaller particles. © 1996 American Vacuum Society.
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