In this research, a procedure was developed for the detection of Cu(II) ions in water using a glassy carbon electrode modified with a nanocomposite of multi-walled carbon nanotubes and a zirconium-based metal-organic framework (MWCNTs/Uio-66(Zr)-NH₂ MOF/GCE). The analysis was performed by differential pulse anodic stripping voltammetry. The excellent sensitivity of the created sensor (MWCNTs/Uio-66(Zr)-NH₂ MOF/GCE) for Cu(II) determination is attributed to the synergy between the strong chelating ability of the terminal amino groups (-NH₂) on the Uio-66 (Zr)-NH₂ MOF for metal ions and the extensive surface area provided by the MWCNTs. The key parameters influencing the stripping current response of Cu(II), namely, pH, accumulation potential, and accumulation time, were systematically studied and optimized. Under optimal conditions, the stripping peak current of Cu(II) ions exhibited a linear relationship with concentration over the range of 0.001 to 10.0 μM. The limit of detection for Cu(II) ions was calculated to be 0.0005 μM. Finally, the MWCNTs/Uio-66 (Zr)-NH₂ MOF/GCE sensor was employed to determine Cu(II) ions in real water specimens, yielding acceptable recovery rates.
Mohammed et al. (Tue,) studied this question.