Effects of Hydrothermal Aging on CO and NO Oxidation Activity over Monometallic and Bimetallic Pt-Pd Catalysts
نویسندگان
چکیده
By combining scanning transmission electron microscopy, CO chemisorption, and energy dispersive X-ray spectroscopy with NO oxidation light-off measurements we investigated deactivation phenomena of Pt/Al2O3, Pd/Al2O3, Pt-Pd/Al2O3 model diesel catalysts during stepwise hydrothermal aging. Aging induces significant particle sintering that results in a decline the catalytic activity for all catalyst formulations. While initial aging step caused most pronounced due to Ostwald ripening, rates further stabilizes at low level activity. Most importantly, observed morphological changes bimetallic sample: 750 °C causes transformation Pt-Pd alloy via core-shell structures into inhomogeneous agglomerates palladium platinum. Our study shines light on behavior noble metal under industrially relevant conditions particularly underscores highly complex treatment.
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ژورنال
عنوان ژورنال: Catalysts
سال: 2021
ISSN: ['2073-4344']
DOI: https://doi.org/10.3390/catal11030300