Square wave voltammetric detection of electroactive products resulting from electrochemical nitrate reduction in alkaline media

The focus of this work is the simultaneous detection of the electroactive species resulting from electrochemical reduction of nitrate (ERN). A simple and fast electroanalytical methodology for the determination of electroactive products resulting from nitrate reduction at a copper electrode in an alkaline media is proposed on the basis of square wave voltammetry (SWV). The obtained results show that, using an adequate pH value, three electroactive species generated from ERN (NO2-, NH2–OH and NH4+) could be electrochemically detected at different applied potentials at a Pt-ring electrode. A comparison of the results obtained by SWV and our previously published cyclic hydrodynamic voltammetry (CHV) measurements was performed. In addition, using both techniques, the conditions for the voltammetric detection of electroactive species resulting from nitrate reduction were established, which will provide useful further information for the ERN process optimization.

► The detection of nitrate reduction products has been studied employing SWV.
► At least three electroactive products can be detected by the SWV technique.
► The stability of the Cu layer in the absence and presence of nitrate is discussed.
► A comparison between the SWV and our previously published CHV results was performed.