Electrochemically active films of negatively charged molecules, surfactant and synthetic clays

The electrochemical behavior of anionic molecules such as hexacyanoferrate and vitamin B12 hexacarboxilate intercalated into clay¯surfactant films is investigated. The results indicate that composites of surfactant cetyltrymethylammonium bromide (CTAB) and synthetic clay facilitate the permeation of the charged molecules through the film. By heating the modified electrode at 120°C for 1 h, the charged molecules, depending on hydrophobic and coulombic forces, are able to accommodate inside the film. Coulombic forces retain the anionic molecules in the clay¯CTAB composite. The films are stable with good electroactivity.