Self-ordering of Au(111) vicinal surfaces and application to nanostructure organized growth

Abstract

This paper reports on Au(111) vicinal surfaces, either regularly stepped surfaces, reconstructed or not, or periodically faceted surfaces, which are well suited to be used as templates for organized growth of clusters. Angles of misorientation with respect to the (111) plane lie between 1 • and 12 • and two opposite azimuths are considered: (i) [211], that leads to steps with {100} microfacets, and (ii) [211], that leads to steps with {111} microfacets. The behaviour of the Au(111) reconstruction in the vicinity of steps depends drastically on the step microstructure, and this is a key point for understanding the various periodic morphologies existing on Au(111) vicinal surfaces. The interaction between the reconstruction and the close-packed steps of the Au(111) surface is interpreted in terms of the relative stability of both types of step. Self-organized morphologies between 10 and 100 nm are interpreted within the framework of elastic theory and by pointing out the crucial role played by the atomic boundary energy term. The microscopic origin of faceting is discussed, proposing two different models depending on each azimuth. Then, we illustrate the use of Au(111) vicinal surfaces as templates for growing long range ordered nanostructures. Examples are given in the case of cobalt growth.

Chromium Nano-Islands on Au(111)

“…1(c). It has been reported earlier for Au(111) that the discommensurate lines become parallel to the step edges with {100} microfacets [13][14][15]. This indicates that the step edges of the Cr islands that are parallel to the discommensurate lines comprise of {100} microfacets.…”

Stabilization of bimolecular islands on ultrathin NaCl films by a vicinal substrate

“…4a shows the surface topography resulting from a deposit of NaCl on a Au (11 12 12) surface held at low-temperature (T $ 95 K). The Au(11 12 12) surface has characteristic 5.8 nm wide Au(1 1 1) terraces separated by straight monatomic steps and periodic truncated ''V"-shape discommensuration lines present at the border between face-centered cubic (fcc) and hexagonal close-packed (hcp) stacking domains [25]. NaCl nucleates at the lower part of step edges where fcc stacking regions are wider.…”

Strain-relief pattern as guide for the formation of surface-supported bimolecular nanoribbons

“…Examples of solid nanotemplates are the natural herringbone reconstruction of Au͑111͒, 6 its vicinal surfaces 7 and self-organized surface patterns occurring in heteroepitaxial systems, 8,9 which have been previously used to influence the formation of molecular as well as atomic assemblies. 4,7,[9][10][11][12][13][14][15][16][17] The triangular strain-relief pattern formed by 2 monolayers ͑ML͒ of Ag on Pt͑111͒ 8 is particularly interesting because the bare terraces of this template surface show a high affinity for the site selective molecular adsorption and for the guidance of homomolecular nanostructures. [14][15][16][17] In this letter, by investigating the case of a bimolecular system on Ag/Pt͑111͒, we demonstrate the possibility of controlling the formation of surface structure-guided heteromolecular nanoassemblies from properly designed molecular building blocks.…”