Harnessing the UiO-67 metal–organic framework for advanced detection of cadmium ions in water bodies

Abstract

Heavy metal ions are hazardous pollutants that pose serious threats to ecosystems and human health, making it imperative to detect and monitor their presence in water for environmental protection. This paper highlights the synthesis of the UiO-67 Metal–Organic Framework (MOF) without any dopants, offering a novel approach specifically for the detection of cadmium ions (Cd²⁺) in aqueous environments. Following solvothermal synthesis, Powder X-ray Diffraction (PXRD), BET nitrogen adsorption–desorption analysis, X-ray Photoelectron Spectroscopy (XPS), and Scanning Electron Microscopy (SEM) were used to characterize the structural and morphological features of UiO-67. The MOF exhibited a high pore volume and surface area, which are essential for enhancing its detection capabilities for Cd²⁺ ions. Based on experimental findings, the proposed sensor exhibits excellent selectivity towards Cd²⁺ ions and a sensitivity of 3.008 μA nM⁻¹. Further, it achieves a low Limit of Detection (LoD) of 1.43 nM μA⁻¹ and a Limit of Quantification (LoQ) of 4.34 nM μA⁻¹. The sensitivity and reliability of the UiO-67-modified electrode are demonstrated by these values, which qualify it for trace-level cadmium ion detection. The ground-breaking potential of undoped UiO-67 serves as a cutting-edge and effective tool for environmental monitoring, particularly in the detection of toxic metal ions in water bodies.