Collect. Czech. Chem. Commun. 1998, 63, 749-760

The Influence of N,N'-Dialkylthioureas on the Two-Step Electroreduction of Zn(II) Ions

Grażyna Dalmata

Faculty of Chemistry, M. Curie-Skłodowska University, 20031 Lublin, Poland


A two-step reduction of Zn(II) ions at the dropping mercury electrode in 1 M NaClO4/0.001 M HClO4 in the presence of N,N'-dialkylthioureas was examined in wide potential and frequency ranges, using the impedance method. The rate constant of the first electron transfer increases with increasing concentration of N,N'-dialkylthioureas, whereas that of the second electron transfer depends largely on the double layer effects, particularly, on the orientation of molecules on the electrode surface.

Keywords: Catalytic activity; Two-step electroreduction of Zn(II) ions; N,N'-Dimethylthiourea; N,N'-Diethylthiourea; N,N'-Diisopropylthiourea; N,N'-Dibutylthiourea; Electrochemistry; Polarography; Dropping mercury electrode.