Abstract: The embedded carbon nanotubes modified bismuth-film electrode was prepared and the electrochemical behaviors of Zn at the modified electrode
was studied with cyclic voltammetry in this work. The result shows that the oxidation peak of Zn at the modified electrode is single and irreversible. The oxidation peak potential (E_pa) and current (I_pa) are -0. 06V and 10. 90 μA respectively, with two protons in this process. Then, the optimum condition of copper differential potentiometric stripping is -1.1 V in accumulation potential, 0. 4 mg/L in bismuth concentrations, and pH 4.6 in the HAc-NaAc buffers. The situ-plate bismuth and standard addition method were used to calculate the concentration of samples. The height of peak is linear with the mass 0 to 50.0 μg/L under the best conditions. The detection limit is 0.84 μg/L. The RSD is 1. 56%∽7. 90% and the recovery rate is in the range between 94.6% and 104.0%.

Key words: words, Zn, carbon nanotubes, bismuth-film, cyclic voltammetry, differential potentiometric stripmethod