Polyelectrolyte-quantum dot multilayer films fabricated by combined layer-by-layer assembly and Langmuir-Schaefer deposition

Stable multilayer thin films, assembled by a combination of layer-by-layer processing of polyelectrolytes and inorganic quantum dot monolayers prepared using the Langmuir-Schaefer deposition procedure, have been examined. Film formation and structure are confirmed using UV-vis absorption measurements and fluorescence spectroscopy. Growth is shown to be linear over several polyelectrolyte-quantum dot multilayers. Films consist of either (trioctylphosphine/trioctylphosphine oxide)-capped CdSe (4.1 nm +/- 0.16 nm) or dodecanethiol-capped An quantum dots (6.0 nm +/- 0.9 nm) within polyelectrolyte bilayers of the well-studied (poly(allylamine hydrochloride)/poly(styrene sulfonate)) system. Electrostatic and hydrophobic interactions combine as the basis for assembly using this versatile new procedure.