Determination of Lead(II) Using Glassy Carbon Electrode Modified with Hexagonal Co3O4 Microparticles

Abstract

In this study, cobaltosic oxide (Co 3 O 4 ) was synthesized by a simple surfactant-free hydrothermal method. The as-prepared materials were characterized by scanning electron microscope and X-ray diffraction, indicating that Co 3 O 4 is formed by stacked hexagonal microsheets. The as-obtained microsheet-stacked Co 3 O 4 was drop-coated on glassy carbon electrode (GCE) to allow the fabrication of electrochemical sensors for the detection of trace Pb 2+ by square wave anodic stripping voltammetry. The proposed Co 3 O 4 /GCE sensors exhibited a linear correlation for Pb 2+ concentration in the concentration range from 0.5 to 5 μM, and the limit of detection was calculated as 1.18×10 -8 M (S/N=3). The results showed that the as-prepared Co 3 O 4 /GCE sensor had good repeatability and sensitivity and the ability to effectively avoid the interference from Cd 2+ and Hg 2+ . In addition, the method for the preparation of proposed sensor was simple and cost effective. Overall, this work provides a promising material for electrochemical detection of heavy metal ions in water.