Application of Nafion/Platinum Electrodes (Solid Polymer Electrolyte Structures) to Voltammetric Investigations of Highly Resistive Solutions

David W. DeWulf
1988 Journal of the Electrochemical Society  
Platinum electrodes on Nation~ 115 membranes, designated Pt/Naf and prepared by an electroless plating method (PtC162-with hydrazine), were used for voltammetric investigations. Scanning electron microscopy (SEM) of these electrodes showed the Pt electrode surface to have the continuous, yet porous, structure necessary for both electronic conduction to the Pt particles and ionic conduction through the membrane/electrode/solution interface. These electrodes were used in the configuration
more » ... nfiguration S/Pt/Naf/H20 + electrolyte, where the counter and reference electrodes were in the aqueous electrolyte solution and the substance of interest was dissolved in solvent, S. Cyclic voltammetry was used to characterize the behavior of several substrates in H20, MeCN, THF, and toluene. Tetracyanoquinodimethane (TCNQ) in acetonitrile (MeCN), tetrahydrofuran (THF), and toluene and benzoquinone (BQ) in THF and toluene could be reduced to anion radicals in the absence of added supporting electrolyte. In THF and toluene, the formation of the radical anion of BQ and TCNQ often involved ion pair formation with alkali metal ion and precipitation. The reduction of TCNQ in toluene in the presence of Na § ions resulted in the formation of the electronically conducting salts, Na+TCNQ -. ABSTRACT A very thin ring electrode (VTRE) inlaid in an insulating glass plane has been fabricated and studied. Its inner radius was 4 mm and its width was 0.7 ~m. Current-potential and current-time behavior for the reduction of ferricyanide in potassium chloride and iodine in excess iodide were studied at the rotating and the stationary very thin ring electrode. Comparison of the electrochemical data with theory indicated that the ring electrode was approximately 0.3 ~m below the surface
doi:10.1149/1.2096191 fatcat:fsfzph6r6zf3nfnsqun7fwenaq