When Fluxionality Beats Size Selection: Acceleration of Ostwald Ripening of Sub?Nano Clusters

نویسندگان

چکیده

Size selection was demonstrated to suppress Ostwald ripening of supported catalytic nanoparticles. When the clusters are subnanometer in size and highly fluxional, such as Pt on rutile TiO2(110) surface, this paradigm breaks down, established theory sintering needs a revision. At temperatures characteristic catalysis (i.e. 700 K), sub-nano thermally populate many low-energy metastable isomers. As these isomers all have different geometric electronic structures, thus, formation dissociation energies (in lieu surface energy), is not suppressed, despite size-selection. However, some arise magic numbers terms stability at ensemble level. Acceleration by species persists though weakens polydisperse cluster systems. We propose competing pathways for sintering, which atomistic level describes found size-specific behavior.

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ژورنال

عنوان ژورنال: Angewandte Chemie

سال: 2021

ISSN: ['1521-3773', '1433-7851', '0570-0833']

DOI: https://doi.org/10.1002/anie.202100107