Self-Assembled Nanostructured Materials

Abstract

The "wet" colloid chemical construction of nanosized or nanostructured materials (i.e., those in the 1−100 nm range) has been inspired by biomineralization (the in vivo formation of inorganic crystals and/or amorphous particles in biological systems) and hierarchically organized self-assembly (spontaneous stepwise assembly of functional units). Subsequent to a summary of the molecular level organization of surfactant monolayers, Langmuir−Blodgett and self-assembled films emphasis is placed on the colloid chemistry underlying the self-assembly of nanostructured materials. Specifically, details are provided on (i) the preparation and stabilization of nanoparticle dispersions, (ii) the adsorption and desorption of nanoparticles onto solid surfaces, and (iii) the nanoreactors provided by polar liquids selectively adsorbed onto solid surfaces from binary polar−apolar liquid mixtures. The "wet" colloid chemical preparation of nanostructured materials in our laboratories is illustrated by the layer-by-layer self-assembly of (i) polyelectrolyte−semiconductor nanoparticle, (ii) polyelectrolyte−clay platelets−semiconductor nanoparticle, and (iii) polyelectrolyte−graphite oxide (and reduced graphite oxide) ultrathin films.