An Electrochemical Sensor Based on Multi-Walled Carbon Nanotubes Functionalized with 2-Picolinyl Hydrazide for Electrochemical Detection of Pb(II) Ions

A new electrochemical sensor was constructed with the nanometer coaxial cable, which was prepared based on Multi-Walled Carbon NanoTubes (MWCNTs) and pyridine. the analysis of trace Pb(II) with Differential Pulse Anodic Stripping Voltammetry (DPASV) was studied. The MWCNTs–TPI–2–Ph was characterized by SEM, TEM, and electrochemical methods. Various parameters such as deposition time, pH values, deposition potential, interference experiment, stability, and reproducibility were investigated. DPASV was used for evaluating the detection of trace Pb(II) based on the accumulation process. Under the optimal conditions, the MWCNTs–TPI–2–Ph/GCE showed excellent stripping response of Pb(II) in the ranges of 1 to 100 μmol/L, the peak currents linearly increased with the concentration of Pb(II). The detection limit was calculated to be 0.03 μM (S/N=3). Detection mechanism for Pb(II) based on MWCNTs–TPI–2–Ph/GCE was proposed. Therefore, it was essential to design an electrochemical sensor based on a new metal ions capture reagent.