Redox-Weak Polyelectrolytes as Electrode Modifiers: Predictions from Molecular Theory

MARIO TAGLIAZUCCHI; CALVO, E.J; IGAL SZLEIFER

Philadelphia

Conferencia; Amer. Chem. Soc., Division of Polymeric Materials: Science and Engineering; 2008

American Chemical Society

The structural and electrochemical properties of electrodes modified with redox-polymers have been studied using a molecular theory. The approach explicitly accounts for the size, shape, charge distribution and conformation of all the molecular species and it includes the excluded volume, van der Waals and electrostatic interactions as well as the charge regulation in the acid and basic species and the oxidized and reduced states of the redox functional groups as a function of the distance from the electrode. The predictions of the theory for the current-voltage cycles under equilibrium conditions are in very good agreement with experimental observations. The effect of pH, solution ionic strength and the coupling that exists between them has been studied. The relationship between the structure of the polymer layer and the electrochemical behavior will be discussed. The ability to tune the properties of the layer by changes in the applied potential, bulk pH and solution ionic strength will be demonstrated.