Facile In Situ Fabrication of ZnO/Zn‐MOF Composite for Sensitive Electrochemical Detection of Cd ²⁺ in Waste Water

ZnO/Zn‐MOF composites were successfully fabricated via a facile in‐situ synthesis strategy, and their electrochemical performances were systematically investigated for the efficient and sensitive detection of Cd 2+ in wastewater. Experimental results demonstrated that the synergistic effect between MOFs and ZnO endowed the composites with an excellent current response toward Cd 2+ . Specifically, MOFs contributed their distinctive large specific surface area, high aspect ratio, and tailorable pore structure, while ZnO provided a high isoelectric point (IEP) and superior electron transport capability. Electrochemical analysis revealed that the Cd 2+ sensing response was dominated by a surface adsorption‐controlled mechanism. Under optimized conditions, the composite‐modified electrode exhibited a favorable linear response to Cd 2+ over the concentration range of 0.5∼200 µM, with a low detection limit of 0.036 µM. Moreover, the as‐prepared sensor also displayed excellent reproducibility, outstanding selectivity, and long‐term stability, collectively verifying the prominent Cd 2+ sensing performance of the ZnO/Zn‐MOF composite electrode.