Lectroreduction of nitrate ions on copper and copper modified by polypyrole electrodes

Abstract

The electroreduction of nitrate ions on copper (Cu) and copper modiefied by polypyrole (Cu/Ppy) electrodes in KCl and NaCl aqueous solutions were studied using cyclic voltammetric (CV) techniques. Nitrate reduction occurred on both electrodes at cathodic potentials of ca. -0,80 V (SCE). Reduction current density reached maximum values at ca. -1,5 V (SCE) on Cu and -1,7 V on Cu/Ppy. In the KCl concentration range from 0 to 0.2 mol/l the reduction current of nitrate increased with KCl concentration. Nitrite was not found as a product of nitrate electroreduction on the Cu/Ppy electrode in studied aqueous solutions.