Simultaneous determination of heavy metals by an electrochemical method based on a nanocomposite consisting of fluorinated graphene and gold nanocage.

Abstract

Fluorinated graphene/gold nanocage (FGP/AuNC) nanocomposite was developed for simultaneous determination of heavy metals using square wave anodic stripping voltammetry. Under optimized conditions, with a buffer pH of 5.0, a deposition potential of - 1.25V, and a deposition time of 140s, the method can obtain the best results. The FGP/AuNC electrode exhibits low limits of detection (0.08, 0.09, 0.05, 0.19, 0.01μgL-1), wide linear ranges (6-7000, 4-6000, 6-5000, 4-4000, 6-5000μgL-1), and well-separated stripping peaks (at - 1.10, - 0.77, - 0.50, - 0.01, 0.31V vs Ag/AgCl) towards Zn2+, Cd2+, Pb2+, Cu2+, and Hg2+, respectively. Furthermore, the FGP/AuNC electrode is also used forsimultaneous determination of Zn2+, Cd2+, Pb2+, Cu2+, and Hg2+ in real samples (peanut, rape bolt, and tea). Highly consistent results are found between the electrochemical method and atomic fluorescence spectrometry/inductively coupled plasma-mass spectrometry. The method has been successfully applied to the determination of heavy metal ions in agricultural food. Graphical abstract Schematic representation of simultaneous determination of heavy metal ions by electrochemical method. The FGP/AuNC (fluorinated graphene/gold nanocage) electrode is used to simultaneous determination of Zn2+, Cd2+, Pb2+, Cu2+, and Hg2+ by square wave anode stripping voltammetry.