Anodic stripping voltammetric determination of trace Zinc(II) using A mercury film electrode

In the present research, to use the advantages of mercury electrode and to avoid exposure to metallic mercury, Mercury film electrode was prepared by chemical deposition of mercury from mercury salt solution on a palladized aluminum electrode [1]. Cyclic voltammetry studies of the Hg/Pd-Al electrode, showed the simultaneous appearance of oxidation and reduction peaks of mercury, indicating the reversibility of the reaction. The effect of concentration and deposition time of palladium and mercury, as well as the pH, type and concentration of the background electrolyte were investigated to provide optimum conditions for zinc(II) measurement in its standard solution using differential pulse anodic stripping voltammetry. The anodic peak currents of Zn2+ was increase linearly with increasing its concentration in the range of 0.1 to 50 μM in acetate buffer with pH=5. Calibration curve with a correlation coefficient of 0.998 and a detection limit of 8×10-8 M was obtained. The present method was successfully applied to determination of zinc(II) in a zinc plus tablet.