Anodic Stripping Voltammetry Using a Vibrating Electrode

Abstract

This work proposes a vibrating microwire electrode as working electrode in stripping voltammetry. The vibration was found to maintain a constant and thin (1 -2 mm) diffusion layer during the deposition step. The electrode vibration eliminated the need for external stirring of the solution, thus facilitating in situ detection in the environment. The vibration was effected by fixing a low-voltage (3 V), asymmetric, electrical rotor to the working electrode (a gold microwire of either 5 or 25 mm). The sensitivity of the vibrated electrode was ca. 22Â greater than stationary. Measurements of copper (4 nM) by anodic stripping voltammetry using the vibrating electrode had a low standard deviation (1% for n ¼ 6) indicating that the diffusion layer had only minor variability. The agitation mechanism was unaffected by water moving at > 2 m s À1 and by water pressure equivalent to a depth of > 40 m, indicating its suitability for in situ measurements. The vibrating probe was used for in situ detection of copper by anodic stripping voltammetry to a depth of 6 m. Using a 5 min deposition time, the limit of detection for labile copper was 38 pM.

Electroanalysis in environmental monitoring: Tracking trace metals—A mini review

“…An initially excellent performance of Au microwire with LOD of 6 and 25 pM for Hg and Cu in model solutions [32] was further improved by using it as a vibrating Au microwire electrode (VGME) [33]. Microwire electrodes of different sizes (5, 10 or 25 µm) were used for determination of traces of Zn, Cd, Pb, Cu, Hg, As, Sb in various environmental samples [19,[34][35][36][37].…”

Determination of Lead and Cadmium in Sea‐ and Freshwater by Anodic Stripping Voltammetry with a Vibrating Bismuth Electrode

“…Previous work using microwire electrodes found that the sensitivity was much improved by using electrode vibration instead of stirring of the solution [17,18]. This electrode was made by fitting a vibrating motor in the polypropylene pipette tip used for the Bi electrode ( Figure 1).…”

Inorganic arsenic speciation by electroanalysis. From laboratory to field conditions: A mini-review

“…(iii) By double concentration [71], reinforced mass transfer [72][73][74] or rapid voltage scanning [28,29,75].…”