Nanoalloy composition-temperature phase diagram for catalyst design: Case study of Ag-Au

TitleNanoalloy composition-temperature phase diagram for catalyst design: Case study of Ag-Au
Publication TypeJournal Article
Year of Publication2012
AuthorsWang LL, Tan TL, Johnson DD
Journal TitlePhysical Review B
Volume86
Pages035438
Date Published07
Type of ArticleArticle
ISBN Number1098-0121
Accession NumberWOS:000306648400015
Keywords1st-principles calculation, alloy nanoparticles, basis-set, dependence, EFFECTIVE CLUSTER INTERACTIONS, ELECTRON-GAS, Gold, STRUCTURAL-CHARACTERIZATION, total-energy calculations, variation formalism, wave
Abstract

By coupling a cluster expansion with density functional theory (DFT) calculations, we determine the configurational thermodynamics (site preferences and occupations) for alloyed nanoparticles (NPs) as functions of composition (c) and temperature (T), exemplified using a 55-atom Ag-Au truncated cuboctahedron NP. The c-T phase diagram for site occupations gives detailed design information for alloyed NP, especially the thermodynamically stable active sites for catalysis and how they change with stoichiometry and processing temperature. Generally, Ag prefers core and Au prefers shell, agreeing with our universal core-shell preference assessed from DFT impurity segregation energies but with interesting multishell configurations having specific active sites.

URL<Go to ISI>://WOS:000306648400015
DOI10.1103/PhysRevB.86.035438
Alternate JournalPhys. Rev. B