Metastable and equilibrium structures on<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Pt</mml:mi></mml:mrow><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:mrow><mml:mi mathvariant="normal">Sn</mml:mi><mml:mn /><mml:mo>(</mml:mo><mml:mn>001</mml:mn><mml:mo>)</mml:mo><mml:mn /></mml:math>studied by STM, RHEED, LEED, and AES

Hoheisel, M.; Kuntze, J.; Speller, S.; Postnikov, A. V.; Heiland, W.; Spolveri, I.; Bardi, Ugo

doi:10.1103/physrevb.60.2033

Cited by 19 publications

(13 citation statements)

References 33 publications

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“…The STM results confirmed the LEED ones and permitted to clarify some structural elements that the analysis based on electron diffraction could not solve [27]. The STM studies were performed on samples treated in the same way (i.e.…”

Section: Pt¢ Sn(001)supporting

confidence: 63%

“…The structure of the c(2x2) phase was found by quantitative LEED to correspond to a simple bulk termination model, as expected [17]. The later STM studies [27] showed that the streaked pattern originates from mesoscopic features, "pyramids" on a relatively flat surface.…”

Section: Pt¢ Sn(001)supporting

confidence: 55%

“…This interpretation is supported by calculations of the local density of states (LDOS) of Pt¢ Sn (Fig. 5) [27]. The LDOS of Sn electronic states is considerably lower at the Fermi-edge compared to the LDOS of Pt.…”

Section: F H G P Imentioning

confidence: 62%

“…Since the characterization of the tip is a long-standing problem in STM the details of this kind of contrast formation are not known at present. However, the Pt-Sn contrast is never observed together with tip changes, such that one may attribute the contrast to the differences in the electronic density of states [27]. One is tempted to relate the tendency of a system to chemical order with the corrugation amplitude in the chemical contrast, because systems with lower chemical order, most often also show lower chemical contrast (e.g.…”

Section: Methodsmentioning

confidence: 99%

“…Quantitative surface crystallographic methods (especially dynamic LEED) have confirmed the LEIS results. The cases where the atomic structure of the topmost layer corresponds to that of a "mixed" bulk crystallographic plane For the L11 phase (fcc, Cu¢ Au type) has been reported, among other cases, for instance for Cu¢ Au(100) ( [56,57,54,58,59,55,60] and Ni¢ Al(100) [52,53] systems which have the same structure and termination as the Pt¢ Sn(100) [17,27]. In all these cases, obviously, the presence of different degrees of outward relaxation ("buckling") for the different chemical species present has been reported.…”

Section: Surface Atomic Structure Of Bulk Pt¢ Sn Alloysmentioning

confidence: 99%

See 4 more Smart Citations

Surface alloys and alloy surfaces: the platinum-tin system

Speller

Bardi

2002

Surface Alloys and Alloys Surfaces

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Section: Pt¢ Sn(001)supporting

confidence: 63%

Section: Pt¢ Sn(001)supporting

confidence: 55%

Section: F H G P Imentioning

confidence: 62%

Section: Methodsmentioning

confidence: 99%

Section: Surface Atomic Structure Of Bulk Pt¢ Sn Alloysmentioning

confidence: 99%

See 3 more Smart Citations

Surface alloys and alloy surfaces: the platinum-tin system

Speller

Bardi

2002

Surface Alloys and Alloys Surfaces

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Ex‐situ surface preparation and analysis: transfer betweenUHVand electrochemical Cell

Hoster¹,

Gasteiger²

2010

Handbook of Fuel Cells

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The further optimization of electrode materials for fuel cells in laboratory studies offers two main approaches: (i) improving the understanding of the microscopic electrode processes by observation with in‐situ and ex‐situ methods; and (ii) the systematic compositional and structural variation of surfaces to create model electrodes for electrocatalytic measurements. The ultra high vacuum (UHV) environment offers unique possibilities for both surface preparation and analysis and has thus been used extensively in recent electrocatalytical research work. At the same time, methods allowing the in‐situ observation of electrochemical processes has also gone through impressive advances in recent years, and in many cases it has been found that earlier ex‐situ results obtained in UHV needed to be revised due to changes of the electrode surfaces during the transfer into UHV. In the following we will discuss some of the most frequently applied ex‐situ methods in electrocatalytic research and review some of the important aspects concerning the reliability of the resulting data. Utilizing a number of examples, we will demonstrate how such combined UHV electrochemistry experiments can be technically realized, including a discussion of commonly encountered practical problems. We will further point out the advantages offered by the electrocatalytical characterization of UHV designed and UHV characterized model electrodes. In our opinion, this is a very promising approach to UHV/electrochemistry experimentation: on the one hand, the uncertainties due to the transfer between UHV and electrochemical environment are less significant compared to emersion experiments of adsorbed adlayers; on the other hand, well‐established UHV preparation techniques combined with structural characterization tools (atomic force microscopy (AFM)/scanning tunneling microscopy (STM)) provide the possibility of precisely tailoring defined model electrodes. Some examples from research on anode catalysts are given to illustrate this unique capability of UHV electrochemistry setups as powerful tool for the systematic tailoring of model electrodes.

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