REACTION OF SOLID CATHODES WITH TETRAALKYLAMMONIUM ELECTROLYTES

This study provides a view of the cathodic processes for Bi, Sn and Pb metals in the presence of two tetraalkylammonium electrolytes: tetramethylammonium (TMA+ ) and dimethylpyrrolidinium (DMP+) tetrafluoroborate. The deposition of an insoluble film at the electrode/solution interface was characterized in all cases using cyclic and linear sweep voltammetry. The new solid phase [tetraalkylam-monium-metal (R4N-metal)] is deposited as a single bulk phase at the Bi electrode, while at Sn and Pb electrodes the deposition process proceeds in two distinct steps: the formation of an initial layer and of the bulk phase. The ease of R4N-metal formation was compared using reduction potentials where R4N-metal products are first observed. The order: Sn > Bi > Pb > Hg, is the same for both cations studied. This suggests that the strength of the metal lattice is important in allowing the formation of R4N-metals. © 1990.