Modeling of chemisorptions is one of the most appealing areas of modern quantum chemistry. The nature and strength of the adsorption bond, its relation with different possible sites on the catalyst, and the influence of the interactions between adsorbate molecules are all basic questions to answer on the way to understanding chemisorption phenomena. The chemisorption of CO on Pd and Rh surfaces and supported particles has been extensively studied experimentally, as CO is very often used as a probe molecule, and the major differences between Rh and Pd catalysts have been pointed out. At similar coverages, the CO adsorption sites and the ordering of the overlayer are different. The hydrogenation of CO yields methanol on Pd catalysts, through a non-dissociative mechanism. In contrast, Rh catalysts can also promote the dissociation of CO, leading to alkane formation. Numerous papers on the chemisorption of CO on supported Rh aggregates have been devoted to the problem of disruption of Rh particles, yielding isolated Rh(CO)2 entities. This phenomenon has also been reported for Ru but has never been mentioned for Pd particles.
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry