THE EFFECT OF SUPPORTING ELECTROLYTE ON THE ELECTROCHEMICAL SYNTHESIS, MORPHOLOGY, AND CONDUCTIVITY OF POLYANILINE

Electrochemical synthesis of polyaniline (PANI) was carried out under cyclovoltammetric conditions using H2SO4, HCl, HNO3, and HClO4 as supp orting electrolytes. The observed different rate of PANI deposit growt h depending on the acid in the solution has been explained on the grou nds of a different degree of specific adsorption for particular anion. It has been found that morphology of the deposit depends greatly upon the anion present in the solution. Thus, PANI synthesized from the so lution of oxyacids results in a dense sponge-like structure while PANI from the hydrochloric acid solution results in a spaghetti-like struc ture. The structure of the deposit influences the conductivity, being higher for a dense deposit from oxyacid solutions and three orders of magnitude lower in case of a deposit from hydrochloric acid solution. (C) 1994 John Wiley & Sons, Inc.