SYMPOSIUM ON SURFACE SCIENCE 2011 Baqueira Beret, Lleida ...

Electrochemical Generation of Low Dimensional Metal
Structures on Top of Self-Assembled Monolayers
Christophe Silien + , Manfred Buck*
EaStCHEM School of Chemistry, University of St Andrews,
North Haugh, St Andrews KY16 9ST, United Kingdom
*mb45@st-and.ac.uk
Low-dimensional metal structures in
contact with molecules being of central
importance for molecular electronics, their
properties are poorly understood at
present. It is not only the difficulty of a
well-controlled preparation but also the
theoretical understanding of the mutual
influence of molecules and metal on their
electronic properties which is at its
infancy. However, studies performed so
far indicate that new opportunities for
Fig. 1: Architecture of a SAM illustrated by the
example of a pyridine (blue) terminated aliphaticaromatic
(grey) thiol (yellow).
tailoring electronic properties arise from the
combination of molecular systems with low
dimensional metal structures [1-3].
One strategy to study metal-molecule systems is
based on self-assembled monolayers (SAMs) as
SAMs offer a rich playground for fundamental
studies due to the combination of properties.
There is, firstly, the enormous flexibility in the
tailoring of SAM properties both with regard to
the surface of a SAM determined by the tail
group and the design of the spacer unit (Fig. 1).
Secondly, using a combination of aliphatic and
aromatic moieties high quality SAMs can be
generated whose surfaces exhibit a crystallinity
closely resembling those of organic single
crystals. Thirdly, charge transfer through SAMs
Fig. 2: a) Illustration of electrochemical metal
deposition on top of a SAM via the reduction of
coordinated metal ions. b) STM image of Pd
metal clusters deposited on a SAM.
+ present address: Materials and Surface Science Institute and Department of Physics, University of Limerick, Ireland
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