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Enhanced catalytic activity of inhomogeneous Rh-based solid-solution alloy nanoparticles

“…This order of catalytic activity may be explained as follows. Generally, Rh is known to be an active catalyst for CO oxidation, whereas Pd and Pt suffer from CO poisoning, which was also demonstrated previously by Kalinkin et al 34,35 Moreover, Park et al found that the CO oxidizing ability of Rh–Pt binary alloy particles could be controlled by changing their composition. 15 In both cases, the activity of pure Rh was found to be much higher than that of pure Pt, whereas the activities of the alloy catalysts were between those of the individual pure metals.…”

Tuning of Catalytic CO Oxidation by Changing Composition of Rh−Pt Bimetallic Nanoparticles

“…18 Our observation that pure Rh nanoparticles are more reactive than Pt nanoparticles is consistent with the CO oxidation results of Kalinkin et al on Rh, Pt, and Rh-Pt alloy thin films at low pressure (<P < 2 × 10 -5 mbar). 19,20 It was found that the activity of the alloy is intermediate between the activities of the individual metals, while a Rh thin film shows much higher activity than a Pt thin film. 20 We can also compare the activity of single-crystal Rh(111) with that of Pt(111).…”

Kinetic Modeling Study of the Oxidation of Carbon Monoxide–Hydrogen Mixtures over Pt/Al2O3and Rh/Al2O3Catalysts

“…The Pt/Rh heterophase catalysts prepared by successive impregnation tend to exhibit a synergistic effect for CO oxidation which was attributed to a selective adsorption effect at different sites (CO on Pt, O 2 on Rh). On the other hand, Pt/Rh alloys tend to present only a monotonic change in reactivity with respect to the catalyst composition. , This change was attributed to the change of surface composition of the Pt–Rh alloy with respect to temperature and gaseous environment. , …”

“…On the other hand, Pt/Rh alloys tend to present only a monotonic change in reactivity with respect to the catalyst composition. 15,16 This change was attributed to the change of surface composition of the PtÀRh alloy with respect to temperature and gaseous environment. 17,18 Several groups have modeled the chemistry involved in multifunctional catalysts using detailed surface reaction mechanisms based on elementary steps.…”