Electrostatically controlled intercalation of Keggin anions into thermally evaporated fatty amine films

A simple solution-based approach for the incorporation of Keggin anions in thin films of octadecylamine (ODA) is described in this paper. The two-step process comprises thermal evaporation of octadecylamine molecules onto solid supports and thereafter immersion of the cationic lipid film into phosphotungstic acid solution. The immersion cycle leads to incorporation of the (PW12O40)(3-) anions in the lipid film through attractive electrostatic interaction with the protonated amine groups of the octadecylamine molecules in the film. The formation of the octadecylamine-Keggin anion complex results in lamellar ordering of the film. (C) 2001 Elsevier Science B.V. All rights reserved.