NON-AQUEOUS ELECTROCHEMISTRY USING OPTICALLY TRANSPARENT ELECTRODES

Tin oxide, gold and platinum film optically transparent electrodes are evaluated for use in spectro-electrochemical studies of organic oxidations and reductions in non-aqueous solvents. Acetonitrile, dimethylformamide, nitromethane, propylene carbonate, dichloroethane, monoglyme and diglyme were used, usually with tetraalkylammonium perchlorate or hexafluorophosphate as supporting electrolyte. Care was taken in purifications and all experiments were run in a controlled atmosphere dry box. The background potential limits for these electrodes depend greatly on the type and purity of solvent and supporting electrolyte, and in well-purified systems are sufficiently large to allow the study of oxidation of benzene or the reduction of phenanthrene or napthalene. Data are reported for the reduction of methyl viologen, a6nthraquinone and three nitroaromatics, and for the oxidation and reduction of several aromatic hydrocarbons. The optical windows of these electrodes have made possible the in situ observation of the intermediates and products of electrode reactions; some examples, including work using rapid scanning spectrophotometry, are presented. © 1969.