Behavior of Polymeric Sulfur Nitride,  (  SN  )  x , Electrodes in Aqueous Media

Abstract

Polymeric sulfur nitride, , has been characterized as an electrode material in aqueous solution by cyclic voltammetry and cyclic chronoamperometry. Background currents, resulting from oxidation and reduction of electrode surface functional groups, were studied in different supporting electrolytes and pH values. A large influence of the nature of the alkali metal cations and Ca2+ of supporting electrolytes on the magnitude of background currents and cathodic breakdown potentials was found. This was interpreted in terms of differences in the interaction strength between these cations and electrode surface functional groups. The ferro‐ferricyanide couple was used to determine relevant electrochemical parameters as well as electrode surface areas. Other redox couples which are active at electrodes are discussed,e.g., Pb2+/Pb0, , quinone/hydroquinone. It was not possible to reduce Cr3+ at electrodes. Furthermore, a dramatic decrease in background currents was observed for Cr3+ electrolyte solutions. The was found to be remarkably stable in aqueous solutions under a wide variety of conditions and a suitable electrode material for chemical modification.