Simultaneous determination of Cd2+ and Pb2+ by an electrochemical sensor based on Fe3O4/Bi2O3/C3N4 nanocomposites
Yuwen Pu, Yalin Wu, Zhihui Yu, Liping Lü, Xiayan Wang
Abstract
The high adsorption capacity of Fe3O4 and C3N4 for heavy metals and the amalgam effect of Bi2O3 were exploited using a Fe3O4/Bi2O3/C3N4-modified glassy carbon electrode (GCE) for the determination of Cd2+ and Pb2+. The electrochemical response performance of the Fe3O4/Bi2O3/C3N4/GCE was studied by square-wave anodic stripping voltammetry. The electrochemical conditions were optimized, including the pH of the buffer solution, content of Fe3O4/Bi2O3/C3N4 on the electrode surface, deposition potential and deposition time. Under optimum conditions, the Fe3O4/Bi2O3/C3N4/GCE sensor shows a linear response from 0.01 μmol/L to 3 μmol/L. The minimum detectable quantity for Cd2+ and Pb2+ are 3 × 10−9 mol/L and 1 × 10−9 mol/L, respectively. Interference studies were carried out. The sensitivity of the Fe3O4/Bi2O3/C3N4/GCE sensor to Cd2+and Pb2+ does not significantly change in the presence of coexisting heavy metal ions. The Fe3O4/Bi2O3/C3N4/GCE sensor exhibits good stability and repeatability. The Fe3O4/Bi2O3/C3N4/GCE sensor was used to detect Cd2+and Pb2+ in river water samples to demonstrate its real-world application.