Voltammetric screen-printed carbon sensor modified with multiwalled carbon nanotubes and bismuth film for trace analysis of thallium(I)

The paper investigates the possibility of using commercially available screen-printed sensors with carbon nanomaterials modified working electrodes to anodic stripping voltammetric determination of trace concentrations of Tl(I). Each working electrode was additionally plated in-situ with a bismuth film (BiF). The highest analytical signal of Tl(I) at potential of -0.65 V (vs. pseudo- reference silver electrode) was achieved at the screen-printed carbon sensor with multiwalled carbon nanotubes and bismuth film modified working electrode (SPCE/MWCNTs/BiF). The calibration curve was linear in the range of Tl(I) concentrations from 1·10^-8 to 1·10^-6 mol·dm^-3 (-0.9 V, 180 s). The developed procedure of Tl(I) determination at this sensor allowed to achieve the low limits of detection and quantification of Tl(I), 2.8·10^-9 and 9.3·10^-9 mol·dm^-3 respectively. The method was used to determine thallium in the spiked water samples from the Vistula river.