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We combined microcontact printing (μCP), the chemical modification of surfaces, and the binding and reduction of metal ions to produce arrays of metal clusters and metal patterns. Pd²⁺ was bound in and at polyamine–amide (PAMAM) dendrimer molecules with potential ligands (amides and amines or carboxylate). Pd clusters formed after reduction. They provided chemically well-defined nuclei for the electroless deposition of metals. After producing a passivation pattern with μCP, deposition occurred only on those pixels or lines that were covered with Pd clusters. The method is quite general, as exemplified by two different passivation examples, alkanethiolate on gold and alkylsilane on oxidized silicon wafers.

We combined microcontact printing (μCP), the chemical modification of surfaces, and the binding and reduction of metal ions to produce arrays of metal clusters and metal patterns. Pd2+was bound in and at polyamine–amide (PAMAM) dendrimer molecules with potential ligands (amides and amines or carboxylate). Pd clusters formed after reduction. They provided chemically well‐defined nuclei for the electroless deposition of metals. After producing a passivation pattern with μCP, deposition occurred only on those pixels or lines that were covered with Pd clusters. The method is quite general, as exemplified by two different passivation examples, alkanethiolate on gold and alkylsilane on oxidized silicon wafers.

Bromine adlayers formed by flame annealing of platinum single crystal surfaces and quenching in bromine vapor were studied by STM and cyclovoltammetry. Bromine forms protective layers which, similar to iodine, prevent contamination of the surface and lead to well-defined surfaces. On Pt(111) a (4 × 4) structure is observed, on Pt(100) a disordered structure, both of which are compatible with densely packed adlayers of bromine. On the Pt(110) surface a complex structure is observed which is similar to that formed by iodine on Pt(110). The reconstructions of Pt(100) and (110) are lifted. Cyclovoltammetric peaks can be attributed to concomitant hydrogen adsorption and bromine desorption; the cyclovoltammograms in bromide electrolyte for clean and for bromine-quenched Pt(111) are identical.

The galvanic deposition of copper on Pt(100)-(1 × 1) was studied in sulfate electrolyte by means of time-resolved in situ STM and voltammetry. Surprisingly, copper grows layer-by-layer in the absence of strongly adsorbing additives. This behavior persists beyond the deposition of two layers and is thus different from that found in analogous vacuum studies. After deposition of 5 to 10 layers, the deposit relaxes to the copper bulk structure. Due to the CuPt misfit and the geometry of the Pt substrate, this results in a square-shaped moirépattern. For thick layers, the growth proceeds in the usual way, i.e. via three-dimensional clusters.