Heavy metal and metalloid electrochemical detection by composite nanostructures

Abstract The purpose of this chapter is to deliver an overview of the available composite nanostructure-based materials used as electrode materials for the electrochemical detection of heavy metals and metalloids. The electrode performances (sensitivity, reproducibility, stability, selectivity, fast response, efficiency in the multiplexed detection, and onsite detection ability) are presented. Due to their special properties and characteristics, the carbon nanocomposite-based electrodes are shown as the most common sensing platforms for heavy metal and metalloid detection. Thus, in four subchapters, the advantages of using graphite, mesoporous carbon, carbon nanotubes (CNTs), and graphene (G) nanocomposites as electrode materials are shown. Among the carbon nanocomposite-based electrode materials, the G-based composite, with different architectures and morphologies, exhibits excellent performances (such as sensitivity, detection limit, selectivity, linear range of detection, stability, repeatability, etc.) for the detection of heavy metals and metalloids. Toxic metal and metalloid electrochemical detection at composite nanostructure-based electrodes facilitates the miniaturization (which leads to sample and reagent volume reduction, lower operational costs, portability, etc.) and automatization of the electrochemical sensors. Moreover, their application field can be extended from environment monitoring to the clinical, safety, defense, and security fields.