Electrochemical characterization of polyaniline-molybdenum trisulfide electrode in non-aqueous media

Polyaniline (PANI)-molybdenum trisulfide (MoS3) electrode, prepared by a mu lti-step procedure, and polyaniline electrode were characterized in non-aqu eous electrolyte (0.5 M LiClO4/acetonitrile) by cyclic voltammetry, electro chemical impedance spectroscopy and the electrochemical quartz crystal micr obalance (EQCM). The voltammetric charge decreased slightly (20%) upon inco rporation of MoS3 in the PANI film electrode. The normalized low frequency capacitance defined as the low frequency capacitance/voltammetric charge ra tio is identical for both PANI and PANI-MoS3 electrodes suggesting that MoS 3 does not contribute to the capacitance measured. The EQCM data is consist ent with mixed transport of anions and cations. Upon oxidation in 0.5 M LiC lO4/acetonitrile, a mass change of 43 g/mol is observed for PANI-MoS3 and t his suggests that solvent is also involved in addition to ClO4- ingress and Li+ expulsion. (C) 2000 Elsevier Science Ltd. All rights reserved.