Positively ionized monolayers of 1,1'-dioctadecyl-4,4-bipyridilium were prepared on aqueous solutions of tetracyanoquinodimethane in a mixed valence state. The floating films were transferred onto ITO electrodes, yielding hybrid multilayers containing both viologen cations and (TCNQ)(2)(-) anions. The electrochemical properties of these modified electrodes were studied by cyclic voltammetry and showed reversible electrochemical processes with quite negative formal potentials of the viologen units. The T-c/T-a ratio was I and the electrochemical activity was preserved beyond the first layer. A comparison study of the hybrid viologen/TCNQ LB films with other films incorporating other counterions was carried out and the differences attributed to chemical complexation and a different arrangement induced by the counterion incorporated in the films. (c) 2005 Elsevier B.V. All rights reserved.