Hybrid materials polypyrrole-heteropolytungstate electrosynthesis of electrodes for secondary batteries

Polypyrroles doped with heterpolytungstate anion [PW12O40](3-) was electrogenerated from acetonitrile solutions. It is found that the productivity of the consumed charge to produce the hybrids always keeps at high constant value of about 1.9 x 10(-3) mg mC(-1), whatever the studied conditions including different potentials, different concentrations of pyrrole, different concentrations of PW12O403- or different temperatures. The hybrid material coats the electrode as a compact, adherent conducting and dark-blue film. The specific charges of the materials initially increase as the polymer weight increases keeping a constant value for greater weight than 0.15 mg cm(-2). Consecutive charge-discharge promotes a fast initial loss of material by solubility, the specific charge of the insoluble part increases until 90 mA h g(-1). Both evolution of the cyclic voltammograms and UV-vis spectroscopies indicate the presence of macroanion in solution after cycling.