title: Correlation between diffusion barriers and alloying energy in binary alloys.
abstract: In this paper, we explore the notion that a negative alloying energy may act as a descriptor for long term stability of Pt-alloys as cathode catalysts in low temperature fuel cells. Using density functional theory calculations, we show that there is a correlation between the alloying energy of an alloy, and the diffusion barriers of the minority component. Alloys with a negative alloying energy may show improved long term stability, despite the fact that there is typically a greater thermodynamic driving force towards dissolution of the solute metal over alloying. In addition to Pt, we find that this trend also appears to hold for alloys based on Al and Pd.
authors.affiliation: DNRF Center for Individual Nanoparticle Functionality (CINF), Department of Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark. schiotz@fysik.dtu.dk and Center for Atomic-scale Materials Design (CAMD), Department of Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Ulrik Grønbjerg
authors.initials: UG
authors.lastname: Vej-Hansen
authors.affiliation: Center for Atomic-scale Materials Design (CAMD), Department of Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark and Department of Chemistry, University of Copenhagen, DK-2100 København Ø, Denmark.
authors.forename: Jan
authors.initials: J
authors.lastname: Rossmeisl
authors.affiliation: DNRF Center for Individual Nanoparticle Functionality (CINF), Department of Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark. schiotz@fysik.dtu.dk.
authors.forename: Ifan E L
authors.initials: IE
authors.lastname: Stephens
authors.affiliation: DNRF Center for Individual Nanoparticle Functionality (CINF), Department of Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark. schiotz@fysik.dtu.dk and Center for Atomic-scale Materials Design (CAMD), Department of Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Jakob
authors.initials: J
authors.lastname: Schiøtz