Electrochemically active films of negatively charged molecules, surfactantand synthetic clays

The electrochemical behavior of anionic molecules such as hexacyanoferrate and vitamin B-12 hexacarboxilate intercalated into clay-surfactant films is investigated. The results indicate that composites of surfactant cetyltrym ethylammonium bromide (CTAB) and synthetic clay facilitate the permeation o f the charged molecules through the film. By heating the modified electrode at 120 degreesC for I h, the charged molecules, depending on hydrophobic a nd coulombic forces, are able to accommodate inside the film. Coulombic for ces retain the anionic molecules in the clay-CTAB composite. The films are stable with good electro activity. (C) 2001 Published by Elsevier Science B .V.