Lead Determination on MWNT/Nafion Composite Modified Glassy Carbon Electrodes

Abstract

Abstract A composite material of nitric acid oxidized multiwalled carbon nanotube (MWNT) and Nafion was prepared. Such composite was modified on a glassy carbon electrode to determine trace of lead by differential pulsed voltammetry. In pH=6.47 NaNO 3 solution, Pb 2+ ions were accumulated on the modified electrode at −0.4 V. Compared with a bare and a Nafion film coated electrode, the composite coated GC electrode can reduce the accumulating potential and eliminate the toxic character of mercury. The calibration plots were linear at low concentration of 5.0×10 −9 –2.0×10 −8 mol/L and high concentration of 2.5×10 −8 –5.0×10 −6 mol/L. The performances characteristics indicate that the electrode can be used to determine trace Pb 2+ ions.