Abstract:
Zirconium based Metal organic framework (UiO-66), Cadmium sulfide (CdS), silver
carbonate (Ag2CO3), binary system CdS/UiO-66, UiO-66/Ag2CO3, CdS/Ag2CO3 and
the ternary CdS UiO-66/Ag2CO3 by sol-gel and co-precipitation method to employ
GCE modified by these materials as electrochemical toxic metals sensors. The
crystanility, structure and composition of the as prepared nanocomposites were
characterized using X-ray diffraction (XRD) pattern, Fourier transform infrared (FTIR)
spectroscopy, and scanning electron microscope (SEM). The electrochemical properties
of different GC modified electrodes on the other hand were investigated by employing
cyclic voltammetry (CV). The XRD result reveals ternary system has lowest particle size
than others Due to the Ternarey Nano have ahighest Band gap energy from others. The
FTIR confirms the formation the expected nanomaterials. The modified GCE by UiO66,
CdS/UiO-66, UiO-66/Ag2CO3,CdS/Ag2CO3and CdS/UiO-66/Ag2CO3 were
characterized using CV. The result demonstrates that binary system nanocomposite
gave a high peak current response with respect to others. This is most probably due to
the catalytic properties of CdS and high surface area of the binary system. The redox
potential of potassium ferrocynide was near to that of its ideal value indicating the
reversibility of the process. The proposed sensor was optimized to identify appropriate
experimental condition for cadmium ion detection. The optimum condition was found to
be pH 4.6 and scan rate 100 mV/s. Under this condition the sensor was tested for the
detection of cadmium in standard solution and exhibits good linearity 2.0 - 8.0 x10-
4mol L−1, sensitivity of 0.00143A mM-1
cm-2
and detection limits 47.1molL-1
(3σ/N).
The result shows that CdS/Ag2CO3 can be a potential candidate for routine analysis of
toxic heavy metals.
