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A polypyrrole (Ppy) film has been deposited on a Ni electrode by anodic polymerisation from acetonitrile solutions. X-ray photoelectron spectroscopy (XPS) analysis shows nickel Ni2+ chemically bound to the polymer chain. Impedance spectroscopy has been employed to characterise this new material in a system of metal/film/electrolyte in a frequency range 105/10−2 Hz. The ac response of the film consists of four or three separable elements depending on the film’s thickness. Incorporation of nickel ions into electronically conducting polymer causes, (i) negligible changes in a polymer redox resistance (high frequency response); (ii) considerable decrease of conductivity responding to ac signal at medium frequency; (iii) linear dependence between resistance measured at medium frequency of ac signal and electrode potential appeared to be caused by nickel presence in the film. Effective diffusion coefficient established for Ppy layers on Ni, Pt and stainless steel at OCV potentials are 1.2×10−10, 1.0×10−8, and 2.2×10−9 cm2 s−1, respectively.

Kinetics and mechanisms for the electrodeposition of lithium from liquid and solid polymer electrolytes formed from lithium salts or from lithium salt complexes have been studied using chronoamperometric and cyclic voltammetric methods at a microelectrode. The type of nucleation and crystal growth process was determined as a function of polymer electrolyte composition. Exchange current densities, coulombic stripping efficiencies and lithium corrosion rates were evaluated.

Process of cathodic deposition of nickel mainly from Ni(BF4)2 solution in DMSO has been investigated using various experimental techniques. It has been found that this process is complicated. The collected experimental data indicate that passivation of fresh cathodic layer of Ni by chemisorption of DMSO molecules takes place. By basing on the rde methods the values of αnm = 0.4 (± 0.05) and kfh = f(Ec) have been estimated.

The process of electroreduction of TiCl 4 in DMSO has been investigated by cyclic voltammetry and rde methods. It has been found that the first step of the cathodic reaction is reduction of Ti(IV) to Ti(III) with α = 0.38 and k f = 6.5210 −4 cms −1 . It has also been found that a secondary chemical reaction follows the TiCl 4 reduction in DMSO. Products of these reactions may behave as inhibitors of cathodic processes and in consequence the rate of the latter decreases. The mechanism of electroreduction of TiCl 4 to Ti(III), Ti(II) and Ti(0) has been suggested. The purpose of the investigation was to determine the effect of solvent type on the kinetics and the mechanism of the electroreduction process of TiCl 4 . The results obtained with the use of acetonitrile (AN) and dimethylformamide (DMF) solutions have been discussed previously ( Electrochim. Acta 25 , 1209 (1980) and Elektrokhimya (1981), in press).

The reaction of electroreduction of TiCl 4 in acetonitrilic solution in the presence of 0.1 M LiBF 4 has been investigated. It has been suggested that processes of reduction-oxidation Ti(IV)Ti(III) proceed relatively easy. The experimental values of and k Ep/2 have been calculated. The mechanism of overall reduction reaction: Ti(IV)Ti(III)Ti(II)Ti(O) has been postulated. It has been found that in the presence of Li + ions in solution the process of chemical Ti(III)Ti(O) reduction can occur