V4C3Tx MXene-modified glassy carbon electrode for the electrochemical detection of cadmium, lead and copper ions

V 4 C 3 T x  MXene/GCE for highly sensitive detection of Cd 2+ , Pb 2+ , and Cu 2+  in water. • LODs of Cd 2+ , Pb 2+ , and Cu 2+  were 2.18 μg/L, 2.02 μg/L and 1.85 μg/L, respectively. • The electrodes possess good reproducibility, storage stability, and selectivity. Water pollution induced by heavy metal ions is growing increasingly severe and endangers human health significantly. Here, a high-performance electrochemical sensor for Cd 2+ , Pb 2+ and Cu 2+ detection in aqueous samples was fabricated by modifying V 4 C 3 T x MXene on a glass carbon electrode (GCE). V 4 C 3 T x was prepared through selective etching, and its structure and chemical compositions were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The results demonstrated that the distinctive two-dimensional lamellar architecture and multivalent vanadium of V 4 C 3 T x MXene provided an ideal platform for efficient heavy metal ion enrichment and electrochemical response. The limit of detection (LOD) was 19.4 nM for Cd 2+ , 9.7 nM for Pb 2+ , and 29.1 nM for Cu 2+ . Besides, the V 4 C 3 T x /GCE was utilized to detect Cd 2+ and Pb 2+ simultaneously, with the LODs to be 24.1 and 12.2 nM. Similarly, the V 4 C 3 T x /GCE was applied for the detection of Pb 2+ and Cu 2+ simultaneously, and the LODs were 12.6 and 34.5 nM, respectively. The V 4 C 3 T x /GCE exhibits excellent repeatability, reproducibility, anti-interference performance and stability, and demonstrates successful application to the analysis of actual water samples. Download: Download high-res image (226KB) Download: Download full-size image