Electrochemical Generation of Solvated Electrons and Hydrogen Evolution in Hexamethylphosphortriamide'"

L Krishtalik, N Alpatova, M Fomicheva
1971 22nd Meeting of the .International Society of Electrochemistry   unpublished
Electrolysis experiments with rotating disc electrodes of copper , amalgamated copper, and platinum in anhydrous hexa-methylphosphortriamide are described. It is shown that the generation of solvated electrons is a primary process. In the same solutions (0.2 M LiCl + 0.09 to 0.20 M HCl) hydrogen evolution occurs as a direct proton discharge step and not through a reaction with the solvated electron(s). Electrochemical generation of solvated electrons is a special, scantily studied, class of
more » ... trochemical reactions. In media in which the stability ' of solvated electrons is high enough, the process of their generation may be relatively easy studied. This study is of interest in several aspects. First, this process is a convenient method to obtain electrons in the bulk of solution. This affords information on the properties of electrons in the condensed phase. Second, this study gives us possibility to establish the mechanism of the generation process itself. Third, by comparing the regularities of generation with those of common electrochemical reactions, we can obtain knowledge of the elementary act mechanism of an electrochemical process. A number of investigators 1-5 suggested that many electrochemical reactions and processes of spontaneous dissolution of metals pass through an intermediate stage of solvated electron formation. The possibility of such a mechanism and the arguments adduced by above authors were questioned by other investigators 6-9 • The object of our study was direct experimental comparison of the two mechanisms: the direct discharge of ions and their reaction with solvated electrons. As the subject of our study we chose anhydrous solutions of LiCl in hexamethylphosphortriamide (0.2 mole/1). Earlier one of the authors together with A. D. Grishina showed 10 that the ESR spectrum of the solvated electron generated electrochemically in LiCl solutions is characterized by a single narrow line. The line width does not depend on the electron concentration, the aggregate state and temperature. This led us to suggest that the small I * Based · on a lecture presented at the