AgAu nanoclusters supported on zeolites: Structural dynamics during CO oxidation
نویسندگان
چکیده
• ITQ2 supported AgAu nanoclusters are active catalysts for CO oxidation. alloyed sites the most centres as they favour reactants adsorption. Different catalyst pretreatments result in different rearrangement of atoms. Nanoclusters evolve during reaction forming and stable catalytic sites. Catalytic tests with situ characterization provides insight into dynamics. The bimetallic nanocluster structure can change pretreatment reaction, thus techniques required a proper analysis In XAFS DRIFTS were used to study dynamic evolution metal Ag x Au 25-x on zeolite activity this was significantly higher than those monometallic 25 nanoclusters. These results explained by formation nanoparticles, which favoured reactant adsorption reaction. Furthermore, initial depended pretreatment, obtaining better conversion, at lower temperatures, pretreated hydrogen oxygen. This also associated an easier alloy under 150 °C. However, alloying process seemed be completed after both cases, i.e . oxygen hydrogen, same performance upon reuse. is constant successive runs, indicating high stability species formed conditions. have shown that combination studies structural dynamics activation
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ژورنال
عنوان ژورنال: Catalysis Today
سال: 2022
ISSN: ['0920-5861', '1873-4308']
DOI: https://doi.org/10.1016/j.cattod.2021.04.016