Square wave anodic stripping voltammetric analysis of lead and cadmium utilizing titanium dioxide/zirconium dioxide carbon paste composite electrode

Recently, our research group has developed a novel carbon paste composite electrode, in which titanium dioxide/zirconium dioxide was incorporated into graphite carbon paste, to detect cadmium and lead in aqueous solution via cyclic voltammetry. In the current work, the newly developed titanium dioxide/zirconium dioxide carbon paste composite electrode was used to quantify lead and cadmium, individually and simultaneously, utilizing square wave anodic stripping voltammetry. In addition to optimization of multiple stripping analysis parameters, trace levels quantification of both metals was attempted. Using the mentioned titanium dioxide/zirconium dioxide carbon paste composite electrode, the detection limits, in modeling solutions, for Pb and Cd were estimated to be 0.48 ppb and 0.77 ppb, respectively. Furthermore, reproducibility of analytical stripping current signal was also calculated and expressed as relative standard deviation for both metals, 3.8% for Cd and 2.5% for Pb (n = 10). The proposed sensor was also tested in river water and well water samples to illustrate its potential for real world application. Moreover, scanning electron microscopy was employed to investigate and characterize the electrode surface morphology.