The Graphene/l-Cysteine/Gold-Modified Electrode for the Differential Pulse Stripping Voltammetry Detection of Trace Levels of Cadmium

Abstract

Cadmium(II) is a common water pollutant with high toxicity. It is of significant importance for detecting aqueous contaminants accurately, as these contaminants are harmful to human health and environment. This paper describes the fabrication, characterization, and application of an environment-friendly graphene (Gr)/l-cysteine/gold electrode to detect trace levels of cadmium (Cd) by differential pulse stripping voltammetry (DPSV). The influence of hydrogen overflow was decreased and the current response was enhanced because the modified graphene extended the potential range of the electrode. The Gr/l-cysteine/gold electrode showed high electrochemical conductivity, producing a marked increase in anodic peak currents (vs. the glass carbon electrode (GCE) and boron-doped diamond (BDD) electrode). The calculated detection limits are 1.15, 0.30, and 1.42 µg/L, and the sensitivities go up to 0.18, 21.69, and 152.0 nA·mm−2·µg−1·L for, respectively, the BDD electrode, the GCE, and the Gr/l-cysteine/gold electrode. It was shown that the Gr/l-cysteine/gold-modified electrode is an effective means for obtaining highly selective and sensitive electrodes to detect trace levels of cadmium.

3D‐printed Metal Electrodes for Heavy Metals Detection by Anodic Stripping Voltammetry

“…3D−Au electrode proposed an 88 % increase in sensitivity compared to GC electrode with the highest current density and steepest calibration curve. Its outstanding sensitivity is in connection with its fast electron transfer kinetics . The sensitivity of 3D−Bi electrode was on a par with GC electrode, where such attractive feature comes from the enhanced nucleation process in multicomponent fusing alloy of Bi and Cd .…”

“…Studies of a greener alternative involve using carbon based electrodes such as glassy carbon (GC) or screen printed carbon electrodes (SPE) and solid electrodes made of inert metals such as gold, silver, platinum, iridium . These electrodes were also modified with metal films, metal affinity compounds or nanomaterials in order to improve the sensitivity , . In particular, gold (Au) and bismuth (Bi) modified electrodes, are available with relatively simple procedures with attractive properties such as good sensitivity and well‐defined stripping signals , combined with their low toxicity.…”

Recent development of eco-friendly nanocomposite carbon paste electrode for voltammetric determination of Cd(II) in real samples

“…In recent years, veritable growing attention has been directed toward voltammetric techniques as powerful and established methods for the analysis of trace cadmium ions in contaminated foodstuffs and biological samples. Among those methods, differential pulse anodic stripping voltammetry (DPASV) [21][22][23][24][25][26][27], linear sweep voltammetry [28,29], adsorptive stripping voltammetry [30][31][32][33][34] and square-wave voltammetry (SWV) [35][36][37][38][39][40].…”