1. Self-assembly of nanoscale lateral segregation profiles.
- Author
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Stania, R., Heckel, W., Kalichava, I., Bernard, C., Kerscher, T. C., Cun, H. Y., Willmott, P. R., Schönfeld, B., Osterwalder, J., Müller, S., and Greber, T.
- Subjects
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INTERMETALLIC compounds , *SURFACE segregation , *BORON nitride - Abstract
The surface segregation profile of an intermetallic compound becomes vertically and laterally modulated upon epitaxial growth of a single-layer hexagonal boron nitride (h-BN) nanomesh. h-BN on PtRh(111) forms an 11-on-10 superhoneycomb, such as that on Rh(111) [Corso et al., Science 303, 217 (2004)], though with a smaller lattice constant of 2.73 nm. X-ray photoelectron diffraction shows that the h-BN layer reduces the Pt enrichment of the first layer by promoting site swapping of about 10 Pt-Rh pairs within the 10?10 unit cell between the first and second layers. This segregation profile is confirmed by density-functional-theory-based cluster-expansion calculations. Generally, a strong modulation of the h-BN bonding strength and a higher affinity to one of the constituents leads to self-assembly of top layer patches underneath the nanomesh pores. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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