An Insight into Ionic Conductivity of Polyaniline Thin Films

The work addresses an issue of the conductivity phenomenon in conductive polymer thin films. Polyaniline was chosen as a broadly used and thoroughly investigated conductive polymer in order to test and show capabilities of the developed original approach based on impedance spectra analysis. A number of films of different thickness were deposited onto a Pt electrode surface and consequently investigated in aqueous solution containing perchloric acid as an electrolyte. The processes that occur in polyaniline film were studied by cyclic voltammetry, electrochemical quartz crystal microgravimetry (EQCM) and electrochemical impedance spectroscopy (EIS). The role of incorporated ions as charge carriers was investigated with respect to the control of the conductivity properties of the film. Along with detailed polyaniline behavior study, the work makes up a fundamental scientific impact on theoretical electrochemistry and electroanalytical techniques.

КИНЕТИКА КАТОДНОГО ВЫДЕЛЕНИЯ ВОДОРОДА НА МОНОСИЛИЦИДЕ МАРГАНЦА В СЕРНОКИСЛОМ ЭЛЕКТРОЛИТЕ

Методами поляризационных и импедансных измерений изучена кинетика реакции выделения водорода на MnSi-электроде в сернокислых растворах с различной концентрацией ионов водорода. Сделано предположение о механизме выделения водорода на силициде. Отмечено влияние тонкой оксидной пленки на кинетику выделения водорода на MnSi при невысоких катодных поляризациях. REFERENCES Rotinyan A. L., Tikhonov K. I., Shoshina I. A. Teoreticheskaya elektrokhimiya [Theoretical Electrochemistry]. Leningrad, Khimiya Publ., 1981, 424 p. (in Russ.) Antropov L. I. Teoreticheskaya elektrokhimiya [Theoretical Electrochemistry]. Мoscow, Vysshaya shkola Publ., 1984, 519 p. (in Russ.) Shamsul Huq A. K. M., Rosenberg A. J. J. Electrochemical behavior of nickel compounds. Electrochem. Soc. , 1964, v. 111(3), p. 270. https://doi.org/10.1149/1.2426107 Vijh A. K., Belanger G., Jacques R. Electrochemical reactions oh iron silicide surfaces in sulphuric acid. 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Mathematical modelling and optimization of the electroplating process with a rotating cathode to reduce the non-uniformity of the coating thickness

The article is devoted to the development of an approach to improving the electroplating uniformity on the cathode surface, rotating around its axis, using a figured anode. A mathematical model of a stationary process with distributed coordinates, based on the equations of theoretical electrochemistry, has been developed for this approach. The problem for optimizing the anode shape according to the criterion for minimizing the non-uniformity of the deposited coating on the rotating cathode is formulated. The results of solving this problem are demonstrated on the example of the Zinc plating. Possible improvements to improve the accuracy of the calculation results for the developed mathematical model are given in the conclusion of the article.

A short introduction to digital simulations in electrochemistry: simulating the Cottrell experiment in NI LabVIEW

A brief introduction to the use of digital simulations in electrochemistry is given by a detailed description of the simulation of Cottrell’s experiment in the LabVIEW programming language. A step-by-step approach is followed and different simulation techniques (explicit and implicit Euler, Runge–Kutta and Crank–Nicolson methods) are applied. The applied techniques are introduced and discussed on the basis of Padé approximants. The paper might be found useful by undergraduate and graduate students familiarizing themselves with the digital simulation of electrochemical problems, as well as by university lecturers involved with the teaching of theoretical electrochemistry.