Title of article :
Step-edge segregation of bimetallic alloys: A LEIS study of Pt25Rh75(4 1 0)
Author/Authors :
B. Moest، نويسنده , , B and Wouda، نويسنده , , P.T and van der Gon، نويسنده , , A.W.Denier and Langelaar، نويسنده , , M.C and Brongersma، نويسنده , , H.H and Nieuwenhuys، نويسنده , , B.E and Boerma، نويسنده , , D.O، نويسنده ,
Issue Information :
هفته نامه با شماره پیاپی سال 2001
Abstract :
We demonstrate that low energy ion scattering can be used to study the step-edge composition on vicinal single crystal surfaces. Employing the shadowing and focusing effects inherent to ion scattering, it is possible to perform site-specific composition measurements on single crystal surfaces over a wide temperature range. By combining these measurements with ion trajectory simulations we have extracted quantitative information concerning the step-edge composition. This technique has been applied to the Pt25Rh75(4 1 0) surface in the temperature range between 400°C and 700°C. The experiments reveal a much stronger Pt enrichment of the step edges than at the terrace sites. This difference between the step-edge composition and the terrace site composition is significantly larger than predicted by simple segregation models based on bond breaking.
Keywords :
Ion scattering spectroscopy , low energy ion scattering , Ion–solid interactions , Alloys , Platinum , Vicinal single crystal surfaces , Rhodium , surface segregation
Journal title :
Surface Science
Journal title :
Surface Science
