An Electrochemical Sensor for Cadmium Ion Detection that is Based on a Aunp-Functionalized Metal-Organic Framework-Graphene Nanocomposite

A Zn metal-organic framework (MOF5) was synthesized successfully by using a simple hydrothermal method. A carbon electrode was modified by utilizing a gold nanoparticle-functionalized MOF5/graphene layer (AuNP@Gr/MOF5 nanocomposite). The AuNP@Gr/MOF5 layer was characterized using FTIR, SEM, EDX, TEM, and XRD. The AuNP@Gr/MOF5 nanocomposite-modified electrode was used for the determination of Cd+2 ions in 0.1 M acetate buffer at pH 4.5 using the SWV technique. The developed sensor exhibited linear behavior in the concentration range of 0.01-25 μM with a limit of detection of 0.005 μM. A good recovery percentage of 102% was achieved in real wastewater samples. The developed sensor showed high selectivity, reducibility, and stability.