ABTS‐Multiwalled Carbon Nanotubes Nanocomposite/Bi Film Electrode for Sensitive Determination of Cd and Pb by Differential Pulse Stripping Voltammetry

A 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonate) diammonium salt (ABTS)-multiwalled carbon nanotubes (MWCNTs) nanocomposite/Bi film modified glassy carbon (GC) electrode was constructed for the differential pulse stripping voltammetric determination of trace Pb2+ and Cd2+. This electrode was more sensitive than ABTS-free Bi/GC and Bi/MWCNTs/GC electrodes. Linear responses were obtained in the range from 0.5 to 35 μg L−1 for Cd2+ and 0.2 to 50 μg L−1 Pb(II), with detection limits of 0.2 μg L−1 for Cd2+ and 0.1 μg L−1 for Pb2+, respectively. This sensor was applied to the simultaneous detection of Cd2+ and Pb2+ in water samples with satisfactory recovery.