Synthesis and Performance of Samarium Vanadate Nanobelt ElectrodeMaterials for Detecting Heavy Metal Ions

Introduction: Cd2+ is a typical heavy metal ion environmental contaminant in the water environment, which causes a variety of diseases owing to its persistent toxicity, even at low concentrations, and its difficult biodegradation. Therefore, great attention has been devoted to developing a sensitive and facile method for the detection of Cd2+. Novel Sm vanadate nanobelts can be used as electrode materials for efficient detection of Cd2+. Methods: Sm vanadate nanobelts with a tetragonal SmVO4 phase were prepared by a facile route and their formation mechanism was analyzed by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Sm vanadate nanobelts act as effective electrode materials for Cd2+ detection in water samples by the square wave voltammetry (SWV) method. Results: Single-crystalline Sm vanadate nanobelts possess flat tips and a smooth surface. The thickness, length, and width of the nanobelts are about 100 nm, a few micrometers, and 400 nm, respectively. An anodic peak for 1 mM Cd2+ at the Sm vanadate nanobelts-modified electrode is at -0.88 V in a 0.1 M PBS buffer solution. The limit of detection (LOD) is 0.21 nM with a linear detection range from 0.01 to 1000 µM. Discussion: pH = 6, 60 s, -0.5 V, and 50 s were determined to be the optimized pH value of the PBS buffer solution, deposition time, deposition potential, and standing time, respectively. Conclusion: The Sm vanadate nanobelts-modified electrode presents excellent stability, reproducibility, and selectivity, which provides a promising and straightforward electrode material to develop an electrochemical sensor for Cd2+ detection in the real water environment.