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Theoretical Study of Ripening Mechanisms of Pd Clusters on Ceria.

ABSTRACT: We carried out density functional theory calculations to investigate the ripening of Pd clusters on CeO2(111). Starting from stable Pd n clusters (n = 1-21), we compared how these clusters can grow through Ostwald ripening and coalescence. As Pd atoms have mobility higher than that of Pd n clusters on the CeO2(111) surface, Ostwald ripening is predicted to be the dominant sintering mechanism. Particle coalescence is possible only for clusters with less than 5 Pd atoms. These ripening mechanisms are facilitated by adsorbed CO through lowering barriers for the cluster diffusion, detachment of a Pd atom from clusters, and transformation of initial planar clusters.

SUBMITTER: Su YQ

PROVIDER: S-EPMC5695895 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Theoretical Study of Ripening Mechanisms of Pd Clusters on Ceria.

Su Ya-Qiong YQ Liu Jin-Xun JX Filot Ivo A W IAW Hensen Emiel J M EJM

Chemistry of materials : a publication of the American Chemical Society 20171013 21

We carried out density functional theory calculations to investigate the ripening of Pd clusters on CeO2(111). Starting from stable Pd n clusters (n = 1-21), we compared how these clusters can grow through Ostwald ripening and coalescence. As Pd atoms have mobility higher than that of Pd n clusters on the CeO2(111) surface, Ostwald ripening is predicted to be the dominant sintering mechanism. Particle coalescence is possible only f ...[more]

PMID: 29170602

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