Antimony powder-modified carbon paste electrodes for electrochemical stripping determination of trace heavy metals

作者：Svobodova Tesarova Eva^*; Baldrianova Lucie; Stoces Matej; Svancara Ivan; Vytras Karel; Hocevar Samo B; Ogorevc Bozidar

来源：Electrochimica Acta, 2011, 56(19): 6673-6677.

DOI：10.1016/j.electacta.2011.05.048

• Non-mercury electrode
• Antimony powder-modified carbon paste electrode
• Anodic stripping voltammetry
• Stripping chronopotentiometry
• Cd(II) and Pb(II)

A new type of the antimony electrode based on a carbon paste bulk-modified with antimony powder (Sb-CPE) is presented for the determination of cadmium(II) and lead(II) ions at the microgram-per-liter concentration level, when using square-wave anodic stripping voltammetric or stripping chronopotentiometric protocol. The Sb-CPE was prepared by mixing fine antimony powder, carbon powder, and silicon oil, thus combining typical features of the carbon paste material with specific electrochemical properties of antimony. Key-operational parameters, including the amount of antimony powder in the carbon paste mixture, effect of the deposition potential and deposition time, were optimized and electroanalytical performance of the Sb-CPE in nondeaerated solution of 0.01 M hydrochloric acid (pH 2) was compared with related bismuth powder-modified carbon paste electrode (Bi-CPE) and with in situ prepared antimony film carbon paste electrode (SbF-CPE). The electrode of interest exhibited well-developed signals and highly linear calibration plots for both metal ions tested. In addition, favorable limits of detection were achieved: namely: 1.4 mu g L(-1) for Cd(II) and 0.9 mu g L(-1) for Pb(II). The applicability of the new electrode was demonstrated on the analysis of tap water (spiked sample). Besides voltammetric measurements, the Sb-CPE was preliminary tested also under chronopotentiometric stripping mode in deoxygenated solutions, revealing also an excellent electroanalytical performance.

• 出版日期2011-7-30