Investigation of electrochemical behavior of Calmagite at a glassy carbon electrode

The voltammetric behavior of 1-(1-hydroxy-4-methyl-2-phenylazo)-2-naphthol-4-sulfonic acid (Calmagite) has been studied by square-wave voltammetry (SWV), differential pulse voltammetry (DPV), cyclic voltammetry (CV) and direct current voltammetry (DCV) in different electrolyte media. The voltammograms recorded at a glassy carbon electrode (GCE) exhibit one cathodic peak, corresponding to the two-step four-electron reduction process of azo compound. The observed shift of the compound reduction peaks to more negative potentials with increasing pH indicates that hydrogen ions are involved in the electrode reaction. The effect of scan rate and pH on the reduction peaks has been studied. From the voltammetric data, the electrochemical reaction mechanism of the azo compound has been suggested.