An investigation on the adsorption characteristics and orientations model of pyrrole on smooth platinum electrode

Since the electropolymerization mechanism is believed to involve the initial adsorption of the monomer on to the electrode surface, in this paper, different criteria for the electroadsorption of pyrrole on a smooth polycrytalline platinum electrode were investigated in different pH media. Experiments were performed in a neutral medium (0.1 M Na2HPO4 + 0.1 M KH2PO4) and an H2SO4 aqueous medium as functions of pyrrole concentration, adsorption time and adsorption potential. The adsorption kinetics and isotherms were studied at constant potential. The number of electrons per occupied site (n(e)) and surface coverage ratios (theta) were calculated. Possible orientation models were proposed for adsorbed species. Copyright (C) 1996 Elsevier Science Ltd