Dioxygen fixation by a cobalt(II)–ammoniacal complex and its electroreduction in a nafion coated solid-state three-electrode cell
Abstract
The reduction potential for the CoII–NH3–O2 system at a glassy-carbon electrode in a solid-state Nafion-coated cell is about 800 mV more positive than obtained for a glassy-carbon–Nafion film electrode when immersed in an aqueous solution containing CoII, ammonia, and dioxygen (+0.3 and –0.5 V vs. Ag/AgCl, respectively); this is attributed to two different electrode reactions: reduction of [(NH3)5Co–O2–Co(NH3)5]4+ in the absence of a contacting liquid electrolyte solution and free O2 in aqueous CoII–ammoniacal solution.