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Stable Oxide Nanoparticle Clusters Obtained by Complexation

J. -F. Berret·A. Sehgal·M. Morvan·O. Sandre·A. Vacher·M. Airiau
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Abstract

We report on the electrostatic complexation between polyelectrolyte-neutral copolymers and oppositely charged 6 nm-crystalline nanoparticles. For two different dispersions of oxide nanoparticles, the electrostatic complexation gives rise to the formation of stable nanoparticle clusters in the range 20 - 100 nm. It is found that inside the clusters, the particles are pasted together by the polyelectrolyte blocks adsorbed on their surface. Cryo-transmission electronic microscopy allows to visualize the clusters and to determine the probability distributions functions in size and in aggregation number. The comparison between light scattering and cryo-microscopy results suggests the existence of a polymer brush around the clusters.

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J. -F. Berret, A. Sehgal, M. Morvan, O. Sandre, A. Vacher, M. Airiau. 2006-08-08. Stable Oxide Nanoparticle Clusters Obtained by Complexation. https://doi.org/10.1016/j.jcis.2006.07.025

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