Exotic high activity surface patterns in PtAu nanoclusters

Abstract
The structure and chemical ordering of PtAu nanoclusters of 79, 135, and 201 atoms are studied via a combination of a basin hopping atom-exchange technique (to locate the lowest energy homotops at fixed composition), a symmetry orbit technique (to find the high symmetry isomers), and density functional theory local reoptimization (for determining the most stable homotop). The interatomic interactions between Pt and Au are derived from the empirical Gupta potential. The lowest energy structures show a marked tendency toward PtcoreAushell chemical ordering by enrichment of the more cohesive Pt in the core region and of Au in the shell region. We observe a preferential segregation of Pt atoms to (111) facets and Au atoms to (100) facets of the truncated octahedron cluster motif. Exotic surface patterns are obtained particularly for Pt-rich compositions, where Pt atoms are being surrounded by Au atoms. These surface arrangements boost the catalytic activity by creating a large number of active sites. © 2013 American Chemical Society.

Citation
Mokkath, J. H., & Schwingenschlögl, U. (2013). Exotic High Activity Surface Patterns in PtAu Nanoclusters. The Journal of Physical Chemistry C, 117(18), 9275–9280. doi:10.1021/jp401466h

Publisher
American Chemical Society (ACS)

Journal
The Journal of Physical Chemistry C

DOI
10.1021/jp401466h

Permanent link to this record