Chế tạo vi điện cực sợi vàng ứng dụng cho phân tích lượng vết Hg(II)

Abstract

The present study has focused on manufacture of gold-wire microelectrode and attempt at using it in detection of Hg(II) by differential pulse anodic stripping voltammetry (DPASV) in electrolyte solution of 0.1 M NaNO₃ + HNO₃ pH = 3. The characteristic of quasi-steady state of the produced microelectrde was obtained with employing a redox Fe²⁺/Fe³⁺ couple in 0.1 M KCl solution. Obtained voltammograms showed the linear relation between the height of oxidation peak of pre-concentrated Hg at potential of 0.7 V and the concentration of Hg(II) in the bulk solution in the range of 1 ppb – 40 ppb with the coefficient efficiency (R²) of 0.995. The limit of detection was 0.056 ppb Hg(II). The error of 3 % was estimated after ten continuous measurements.

Keywords. Gold wire microelectrode, mercury detection, trace concentration.