Mercury(II) trace detection by a gold nanoparticle-modified glassy carbon electrode using square-wave anodic stripping voltammetry including a chloride desorption step

Abstract

Gold nanoparticles (AuNPs) were deposited on a glassy carbon (GC) substrate by constant potential electrolysis and characterized by cyclic voltammetry in H2SO4 and field emission gun scanning electron microscopy (FEG-SEM). The modified AuNPs-GC electrode was used for low Hg(II) concentration detection using a Square Wave Anodic Stripping Voltammetry (SWASV) procedure which included a chloride desorption step. The comparison of the obtained results with our previous work in which no desorption step was used showed that this latter step significantly improved the analytical performances, providing a three time higher sensitivity and a limit of detection of 80pM for 300s preconcentration, as well as a lower average standard deviation. The influence of chloride concentration on the AuNPs-GC electrode response to Hg(II) trace amounts was also studied and its optimal value confirmed to be in the 10(-2)M range. Finally, the AuNPs-GC electrode was used for the determination of Hg(II) in a natural groundwater sample from south of France. By using a preconcentration time of 3000s, a Hg(II) concentration of 19±3pM was found, which compared well with the result obtained by cold vapor atomic fluorescence spectroscopy (22±2pM).

Diamond Electrodes for High Sensitivity Mercury Detection in the Aquatic Environment: Influence of Surface Preparation and Gold Nanoparticle Activity

“…A bare BDD control electrode confirmed insufficient activity for effective sensing at any of the mercury concentrations measured here. Hg 0 was pre‐concentrated onto the working electrode surface by application of 0.35 V for 10 min . A SWASV scan from 0.35 to 1.1 V with a 0.005 V potential step, 0.01 V amplitude and 10 Hz frequency was then applied, as has been shown to be optimal .…”

A New Sensor with Increased Lifetime Based on a Mixed Diazonium Thick Film/Gold Nanoparticles Interface for Hg(II) Trace Detection

“…Hg(II) detection was performed using a previously reported square wave anodic stripping voltammetry (SWASV) procedure [7].…”

Recent Advances and Perspective on Design and Synthesis of Electrode Materials for Electrochemical Sensing of Heavy Metals

“…Metal nanoparticles and metal oxide‐based electrodes have been the subject of recent researches due to their specific physicochemical properties of enhanced diffusion of electroactive species, improved selectivity, catalytic activity, and higher signal‐to‐noise ratio, where cuprous oxide and bimetallic nanoparticles (iron with palladium, gold, silver, and platinum) were used ubiquitously. Nanomaterials based on gold nanoparticles have been tremendously used for the sensitive electrochemical determination of heavy metals . The determination of mercury with a detection limit of 80 p m and wide linear range of 0.4–4 n m has been realized with Au NPs as functional material on GC substrate .…”

“…Nanomaterials based on gold nanoparticles have been tremendously used for the sensitive electrochemical determination of heavy metals . The determination of mercury with a detection limit of 80 p m and wide linear range of 0.4–4 n m has been realized with Au NPs as functional material on GC substrate . Au NPs has also been used a surface modifier of a commercial screen‐printed gold electrode (SPGE) for simultaneous detection of Pb and Cu.…”