Development of electrochemical sensors for heavy metal ions and their uses

• Main Author: Naqibah Samsuri
• Other Authors: School of Chemical and Biomedical Engineering
• Format: Final Year Project
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Bioengineering
• Online Access: http://hdl.handle.net/10356/61636
• Institution: Nanyang Technological University

Excessive levels of heavy metals or even small doses of very toxic heavy metals can be damaging to the health and the environment. The sensitive and selective detection of trace toxic heavy metals are necessary due to their adverse toxic risks to human health at very low concentrations. This study reports the modification of glassy carbon electrode (GCE) with graphene and subsequently with metal nanoparticles (NPs), the characterization of the modified GCE and its electrochemical applications for the detection of heavy metal ions. A polydopamine (PDA)-based approach is used to develop an electrochemical sensor of core-shell bimetallic nanocrystals which will be loaded onto a graphene-based electrode. The Au@Ag@PDA-graphene electrodes are utilized for the simultaneous electrochemical determination of trace levels of cadmium (Cd2+) and lead (Pb2+). The impact of chemical composition of the NPs and its loading onto graphene on the performance of the electrochemical sensor are examined and discussed. Differential pulse voltammetry studies revealed that Cd2+ and Pb2+ were simultaneously stripped with well-defined, separated and sharp peaks for Cd2+ and Pb2+. Low detection limit was also observed for Cd2+. This study suggests that Au@Ag@PDA-graphene is a promising material for the fast and accurate detection of trace heavy metal ions.