Determination of Cadmium (II) Ions in Environmental Samples : A Potentiometric Sensor

Abstract

A sensor electrode was modified by multi-walled carbon nanotubes functionalized by dithizone. The electrode was used for determination of trace amounts of cadmium (II) ions. The electrode composition was 67% graphite powder, paraffin 23%, 10% modified MWCNTs (W/W). The linear range for lead (II) was 1.8×10 -7 to 1.0×10 -4 mol L "1 and the limit of detection was obtained 1.0×10-7 mol L "1 . The lifetime of the electrode was 12 weeks and a fast response time was observed. The electrode was used for determination of trace amounts of Cd(II) ions in standard reference materials of water and soil.