Activity Report 2010 - CNRS

TERPYRIDINE-BASED
MACROCYCLES FOR
SWITCHES
HIGHLIGHT : MOLECULAR ELECTRONICS
The POLYSUPRA project , coordinated by
Guy ROYAL (DCM, UJF) with Pierre
TÉRECH (INAC/SPrAM) and Eric
JALAGUIER, Julien BUCKLEY (Léti) as copartners
concerns the preparation and
study of self-assembled coordination
polymers whose originality is to be able
to respond to an external input (stimulus)
that can be optical, electrical or chemical.
The proposed systems are
macromolecules based on polytopic
ligands containing two coordinating units
(terpyridines) bridged by a spacer having
particular redox, optical or chemical
properties. (Fig. 1) These molecules are
particularly attractive for the preparation
of smart materials or for electronic
devices (transistors, memories).
Fig. 1: Schematics detailing the formation of
self-assembled metallo-polymers. The spacer
induces additional chemical properties.
The objectives of POLYSUPRA project
supported by the Foundation are: i) the
preparation and study of new
metallopolymers; ii) the structural
characterization of the polymers; iii) the
attachments of the polymers onto solid
substrates and study of the modified
surfaces and iv) the incorporation of the
systems into electronic devices. At of
spring 2011, the first three tasks have
been successfully realized.
Fig. 2: Electrochromic behavior of a cobalt
polymer.
Structural and Rheological switching
characterization of the polymers and their
attachment onto solid substrates
These metallopolymers can also form
solution or gels, depending on the
experimental conditions and it has been
shown that a reversible gel to liquid
conversion can be electrochemically
controlled by changing the oxidation
state of the metal ions in the polymers
chains (Fig. 3). These polymers have
been characterized using rheology,
viscosimetry and SANS experiments.
Their grafting onto solid substrates is also
under way.
Ox
Red
Fig. 3: Redox controlled Gel/Liquid conversion
CONTACT
guy.royal@ujf-grenoble.fr
FURTHER READING
A. Gasnier et al, Langmuir, 25(15), 8751–
8762 (2009)
A. Gasnier, et al., Inorganic Chemistry, 49,
2592 (2010)
Synthesis and study of the
metallopolymers in solution.
Some polynuclear metallopolymers
incorporating a binding unit as spacer
have been prepared and investigated.
These electroactive materials originally
incorporate different types of metal
complexes in the same polymer chain
which induces novel functionalities.
For example, remarkable electrochromic
properties have been demonstrated (see
Fig. 2).
Fig. 4: Cover of the march 2010 issue of
Inorganic Chemistry featuring the first phase
of work supported by this RTRA project.
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