Magnetic nanoparticles are of great interest for researchers from

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					                                   NANOPARTICLES
                                         G. Pourroy
Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 CNRS-ULP, 23 rue
                            du Loess, 67034 Strasbourg, France

Magnetic nanoparticles are of great interest for researchers from a wide range of disciplines,
including magnetic fluids, catalysis, biotechnology/biomedicine, magnetic resonance imaging,
data storage, and environmental remediation. The properties of fine magnetic particles are
dominated by surface effects, finite size effects and interaction effects. Therefore, successful
applications of nanoparticles are highly dependent on the control of their composition, size,
and stability under a range of different conditions. For instance, naked metallic nanoparticles
are chemically highly active, and are easily oxidized in air, resulting generally in loss of
magnetism and dispersibility. Nanoparticles also tend to form agglomerates to reduce the
energy associated with their high surface area to volume ratio.
We will first focus on suitable methods that have been developed for the synthesis of
magnetic nanoparticles, then on structural and chemical characterizations generally used, and
on the different effects occurring in magnetic nanoparticles such as superparamagnetism,
blocking temperature... The strategies developed to stabilize, protect or functionalize, grafting
or coating the nanoparticles, will be presented. Applications will be developed.