Determination of Trace Metals by Anodic Stripping Voltammetry Using a Carbon Nanotube Tower Electrode

Anodic stripping voltammetry (ASV) trace detection of the heavy metals ions Pb(2+), Cd(2+), Cu(2+) and Zn(2+) was done at highly aligned multi-wall carbon nanotube tower electrodes (CNT tower electrodes). The CNT tower electrode is one type of CNT array that consists of millions of ordered super long CNTs. Osteryoung square-wave stripping voltammetry was used for the stripping step. This electrode material shows good resolution for individual detection of these four metal ions with calculated detection limits of 12 nM, 25 nM, 44 nM and 67 nM for Pb(2+), Cd(2+), Cu(2+) and Zn(2+), respectively, for a deposition time of 120 s. The detectable limit was as low as 0.5 nM for a 10 min deposition.