Recent Advances in Anodic Stripping Voltammetry with Bismuth-Modified Carbon Paste Electrodes

Abstract

In this article, the results of some recent investigations on two types of bismuth-modified carbon paste electrodes are presented. In the first study, the bismuth-film carbon paste electrode (BiF-CPE) operated in situ and employed in anodic stripping voltammetry of Cd(II) and Pb(II) at the low mg L À1 level was of interest in view of choosing the proper Bi(III)-to-Me(II) concentration ratios (where Me: Pb or Cd). Such optimization has resulted in significant improvement of detection limits down to 1.0 mg L À1 Cd and 0.8 mg L À1 for Pb, which allowed us to apply the BiF-CPE for analysis of selected real samples of tap and sea water. The BiF-CPE was also further investigated for its application in highly alkaline media. In this case, attention was focused on the complex-forming capabilities of the OH -ions and their effect on the anodic stripping characteristics of some heavy metals (i.e. Cd, Pb, Tl) as well as upon the formation of the bismuth film itself. The last example deals with the continuing characterization of the recently introduced carbon paste electrodes modified with bismuth powder (Bi-CPEs) which combine the advantageous properties of carbon paste material with the favorable electrochemical properties of bismuth. Three series of electrodes, differing either in the content of metallic bismuth (from 8 to 50% w/w) or in the type of the carbon powder used (two spectroscopic types of graphite and powdered glassy carbon), were compared and the respective relations to the optimal carbon paste composition evaluated. Attractive electroanalytical performance of the Bi-CPE in anodic stripping voltammetry is demonstrated for selected model mixtures of heavy metals (Mn, Zn, Cd, Pb, Tl, and In).

Electroanalytical Determination of Cadmium(II) and Lead(II) Using an in-situ Bismuth Film Modified Edge Plane Pyrolytic Graphite Electrode

“…It has been shown that bismuth film electrodes have the same advantages as mercury film electrodes and at the same time, due to the negligible toxicity of bismuth, they are also environmentally friendly. [6][7][8] Various types of bismuth modified electrodes have been utilized for the determination of heavy metals using stripping analysis methods. Bismuth is used for the modification of different kinds of carbon based electrodes such as carbon paste electrodes, 6,9-11 carbon fiber electrodes, 8 graphite epoxy composite electrodes, 12,13 carbon nanotube nanoelectrode array, 14 carbon film electrodes, 15,16 boron doped diamond 17 and particularly glassy carbon electrodes.…”

Highly Sensitive Determination of Cadmium and Lead Using a Low-cost Electrochemical Flow-through Cell Based on a Carbon Paste Electrode

“…Indeed, the optimum Bi 3+ concentration has been evaluated for the complete formation of multi-component alloys, 25 the prevention of a high hydrogen evolution rate at negative potentials and the saturation effect of Bi-film on the surface of CPE. 16,18,26,27 As reported by Švancara et al, 16 the Bi 3+ concentration must be 10 times higher than the target analyte concentration to avoid a saturation effect. Thus, a concentration of 5 mg dm -3 was used as the optimal Bi 3+ concentration in the preparation of the CPE for this in-house designed thin-layer flow cell.…”

Pyrolyzed Photoresist Carbon Electrodes for Trace Electroanalysis of Nickel(II)

“…Bismuth electrodes have been successfully applied in anodic [20][21][22] and cathodic or adsorptive stripping voltammetry (AdCSV) [23,24]. The latter technique relies on the interfacial accumulation of a complex of the target metal on the surface of the working electrode; this is an interesting approach, especially when the analyte cannot form an amalgam/alloy [25][26][27].…”