Bismuth film-modified gold (Au) electrodes were prepared by an ex-situ and in-situ plating for the simultaneous determination of a trace level of lead (Pb2+) and cadmium (Cd2+) ions by anodic stripping voltammetry. The effects of several key operational parameters in the electrochemical deposition of Bi3+ ion on a Au substrate, such as the concentration and deposition time of Bi3+ ion, preconcentration time, pH of supporting electrolyte, and the stripping potential scan mode, were optimized. Pb2+ and Cd2+ ions formed alloys with bismuth and displayed well-defined peaks in differential pulse stripping voltammetry. Following a 180 s preconcentration, the calibration graphs were linear over the 5-300 and 10-160 μg/L ranges of the ions for ex-situ and in-situ Bi filmmodified electrodes (BiFE), respectively, and the lower detection limits were down to μg/L level. The modified electrodes were applied to the determination of Pb2+ ion in vegetables.
- Anodic stripping voltammetry
- Bismuth film electrodes
- Gold electrode
- Heavy metals
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Electrical and Electronic Engineering