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Alloying and Structure of Ultrathin Gallium Films on the (111) and (110) Surfaces of Palladium.

ABSTRACT: Growth, thermal stability, and structure of ultrathin gallium films on Pd(111) and Pd(110) are investigated by low-energy ion scattering and low-energy electron diffraction. Common to both surface orientations are growth of disordered Ga films at coverages of a few monolayers (T = 150 K), onset of alloy formation at low temperatures (T ? 200 K), and formation of a metastable, mostly disordered 1:1 surface alloy at temperatures around 400-500 K. At higher temperatures a Ga surface fraction of ?0.3 is slightly stabilized on Pd(111), which we suggest to be related to the formation of Pd₂Ga bulk-like films. While on Pd(110) only a Pd-up/Ga-down buckled surface was observed, an inversion of buckling was observed on Pd(111) upon heating. Similarities and differences to the related Zn/Pd system are discussed.

SUBMITTER: Stadlmayr W

PROVIDER: S-EPMC3786520 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Alloying and Structure of Ultrathin Gallium Films on the (111) and (110) Surfaces of Palladium.

Stadlmayr Werner W Huber Veronika V Penner Simon S Klötzer Bernhard B Memmel Norbert N

The journal of physical chemistry. C, Nanomaterials and interfaces 20130902 38

Growth, thermal stability, and structure of ultrathin gallium films on Pd(111) and Pd(110) are investigated by low-energy ion scattering and low-energy electron diffraction. Common to both surface orientations are growth of disordered Ga films at coverages of a few monolayers (<i>T</i> = 150 K), onset of alloy formation at low temperatures (<i>T</i> ≈ 200 K), and formation of a metastable, mostly disordered 1:1 surface alloy at temperatures around 400-500 K. At higher temperatures a Ga surface f ...[more]

PMID: 24089625

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