Enhancing selectivity in stripping voltammetry by different adsorption behaviors: the use of nanostructured Mg-Al-layered double hydroxides to detect Cd(II).

We report the use of nanostructured layered double hydroxides (LDHs) for the highly selective and sensitive detection of Cd(2+) using anodic stripping voltammetry (ASV). In particular, the modification of a glassy carbon electrode promotes the sensitivity and selectivity towards Cd(2+) in the presence of Pb(2+), Hg(2+), Cu(2+) and Zn(2+). The electrochemical characterization and anodic stripping voltammetric performance of Cd(2+) were evaluated using cyclic voltammetry (CV) and square wave anodic stripping voltammetry (SWASV) analysis. Operational parameters, including supporting electrolytes, pH value, deposition potential and deposition time were optimized. In addition, the selectivity, interference and stability were also investigated under the optimized conditions. The results showed that the fabricated electrode possessed good selectivity, stability and reproducibility. The proposed electrochemical sensing strategy is thus expected to open new opportunities to broaden the use of ASV in analysis for detecting heavy metal ions in the environment.