Construction of a highly sensitive Cd(II) and Pb(II) simultaneous detection electrochemical sensor based on CNTs/UiO-66-NH₂@AuNPs composite material

The creation of dependable analytical platforms capable of detecting multiple heavy metal ions (HMIs) concurrently continues to be a significant challenge in environmental monitoring. This study introduces an innovative composite sensing material composed of gold nanoparticles (AuNPs) modified UiO-66-NH 2 metal organic frameworks (MOFs) and carbon nanotubes (CNTs) for simultaneous detection of multiple HMIs. UiO-66-NH 2 , with its extensive specific surface area and three-dimensional porous framework, facilitates effective ion diffusion and target preconcentration. The interconnected CNTs network significantly enhances electron transfer kinetics and expands the electroactive surface area, as confirmed by cyclic voltammetry (CV) analyses. AuNPs can effectively amplify electrochemical reactions and enhance the sensitivity of electrochemical detection. The thoughtful design of this sensing material amalgamates the unique benefits of its constituents. This sensing material attains remarkably low limits of detection (LOD), which is 0.021 μg·L −1 for Cd 2+ and 0.008 μg·L −1 for Pb 2+ , showcasing outstanding resistance to interference in complex environments. The potential applicationsapplications of MOF-based composites in the electrochemical sensors of HMIs are expanded by this methodology.