Electroreduction of Mo(VI) Compounds in Ammonium–Acetate Solutions

V. V. Kuznetsov V. V. Kuznetsov , M. A. Volkov M. A. Volkov , D. A. Zhirukhin D. A. Zhirukhin , E. A. Filatova E. A. Filatova
Российский электрохимический журнал
Abstract / Full Text

The kinetics of cathodic reactions in ammonium acetate solutions proposed for electrodeposition of metallic molybdenum was studied. The reduction of molybdenum compounds in the oxidation state +6 was found to occur stepwise according to the scheme Mo(VI) → Mo(V) → Mo(III). The waves observed on the polarograms are complicated by adsorption effects. The reduction of molybdenum to the metallic state is possible only at high negative potentials of the cathode; under the polarographic analysis conditions, this wave was not recorded. The deposit that formed on the surface of the solid cathode during cathodic polarization (i = 0.5 A cm–2) contains both molybdenum in the metallic state and molybdenum oxides. The ratio between the electrolysis products depends on the temperature of solution: a decrease in the temperature leads to an increase in the amount of metallic molybdenum.

Author information
  • Mendeleev University of Chemical Technology of Russia, Moscow, 125047, Russia

    V. V. Kuznetsov, M. A. Volkov, D. A. Zhirukhin & E. A. Filatova

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