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Technical University of Crete
Technical University of Crete
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| URI: | http://purl.tuc.gr/dl/dias/0ABAF449-5706-444A-85EC-4F42591D9840 | ||
| Year | 2011 | ||
| Type of Item | Peer-Reviewed Journal Publication | ||
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| Bibliographic Citation | V. Matsouka, M. Konsolakis, I.V. Yentekakis, A. Papavasiliou, A. Tsetsekou, N. Boukos ," Thermal aging behavior of Pt-only TWC converters under simulated exhaust conditions: Effect of rare earths (CeO2, La2O3) and Alkali (Na) modifiers," Topics in Catalysis, vol. 54, no. 16, pp. 1124-1134, Nov. 2011. doi: 10.1007/s11244-011-9734-6 https://doi.org/10.1007/s11244-011-9734-6 | ||
| Appears in Collections |
In the present work, the feasibility to design monometallic (Pt-only), low metal loading (0.1 wt% Pt) three-way catalytic converters (TWCs), with comparable catalytic efficiency and thermostability to that of commercial bimetallic Pt/Rh TWCs has been explored. It is shown that this can be accomplished by modifying Pt/γ-Αl2O3 washcoat of TWC via two different methods of promotion: support-mediated promotion by modifying the γ-Al2O3 support with rare earth structure-modifiers (CeO2–La2O3) and surface-induced promotion by directly modifying the Pt surface with alkalies (e.g., Na), producing a doubly-promoted Pt(Na)/Al2O3-(CeO2–La2O3) TWC. The catalytic performance of as prepared TWCs in comparison to that of a commercial bimetallic (Pt–Rh) TWC, under simulated exhaust conditions at the stoichiometric point appears to be superior, even after severe thermal treatment at 900 °C for 5 h in air and despite the fact that the latter contain 4.5-fold higher noble metals loading. Moreover, the evolution of structural, textural and surface behavior of aged catalysts was identified by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy and diffuse reflectance infrared Fourier transform spectroscopy and appropriately correlated with the catalytic performance and thermostability of TWCs.
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