Aniline-mediated synthesis of carboxymethyl cellulose protected silver nanoparticles modified electrode for the differential pulse anodic stripping voltammetry detection of mercury at trace level

Single-pot synthesis of carboxymethylcellulose-protected silver nanoparticles (CMC@AgNPs) was investigated using aniline as a reducing agent. Polymer matrix-embedded nanoparticles were synthesized by two different experimental conditions, namely under reflux and at room temperature. Similarly, a control experiment was carried out using polyvinylpyrrolidone as stabilizing agent under identical experimental conditions. Resulting AgNPs were isolated and characterized by UV–Vis, FT-IR, and SEM to identify shape, size, and type of capping action. CMC-capped AgNPs were octahedron-shaped whereas PVP-capped exhibited a core–shell kind of capping similar to a nested protection of AgNPs. The electrochemical property of the modified electrode was studied using electrochemical impedance spectroscopy and cyclic voltammetry. Electrochemical detection of Hg2+ was investigated using CMC@AgNPs/GCE with an enhanced peak current as noted by DPASV method. Detection limit was found to be 0.19 nM, and its linear ranges were between 5 and 75 μM based on signal-to-noise ratio (S/N = 3). The present system can be utilized for the determination of Hg2+ in water samples at low-concentration ranges.