ELECTROCHEMICAL INVESTIGATIONS ON POLY(PHENYLENE-1,3,4-OXADIAZOLES)

The electrochemical n-doping processes of poly(p-phenylene-1,3,4-oxadiazole) and poly(m-phenylene-1,3,4-oxadiazole) (p-POD, m-POD respectively) in acetonitrile with LiClO4 and Bu4NClO4 salts have been studied. Cyclic voltammograms and impedance spectra were measured to characterize the charge and discharge properties of the films obtained from poly(p/m-phenylene-1,3,4-oxadiazole) on glassy carbon, Pt and ITO glasses. In addition u.v. absorption measurements of p-POD coated ITO glasses were carried out. n-doping of p-POD was easy but m-POD was electrochemically inactive in the potential range under study. The AC impedance method was used to estimate the apparent diffusion coefficient (D(app)) of BuN+ counter ions in p-POD films. The values obtained are of the order 10(-7) cm2 sec-1. We believe that this is the first time that D(app) values in p-POD have been published.