Sensitive detection of Pb ions by square wave anodic stripping voltammetry by using iron oxide nanoparticles decorated zinc oxide nanorods modified electrode

Abstract

In this work, zinc oxide nanorods (ZnONRs) and Fe2O3 nanoparticles (Fe2O3NPs) were developed on indium tin oxide (ITO) as an Fe2O3NPs/ZnONRs/ITO electrode, and its performance for lead (Pb) ion detection in the aqueous phase was evaluated. Field-emission scanning electron spectroscopy (FESEM) and X-ray diffraction (XRD) were performed to determine the morphology and phases of the samples, respectively. Results confirmed the successful fabrication of the Fe2O3NPs/ZnONRs/ITO electrode. The FESEM and transmission electron microscopy (TEM) showed that the ZnONRs and Fe2O3NPs had diameters of 60–90 nm and ~17 nm, respectively. The performance of the Fe2O3NPs/ZnONRs/ITO electrode for Pb ions detection was evaluated using electrochemical analysis; cyclic voltammetry and square wave anodic peak voltammetry methods. The Fe2O3NPs/ZnONRs/ITO electrode showed the lowest limit of detection and sensitivity of 0.01 μM and 4.40 μA μM−1, respectively, within the linear dynamic range from 0.2 μM to 1.2 μM. The applicability of the Fe2O3NPs/ZnONRs/ITO electrode was tested using a real seawater sample. Results were comparable with those detected using inductively coupled plasma optical emission spectrometry, indicating the excellent performance of the Fe2O3NPs/ZnONRs/ITO electrode. The Fe2O3NPs/ZnONRs/ITO-modified electrode offers a cheap, fast, and simple detection for Pb ions.