Fabrication of MOF-177 for electrochemical detection of toxic $$\hbox {Pb}^{2+}$$ and $$\hbox {Cd}^{2+}$$ ions

Abstract

We have studied the electrochemical behaviour of room-temperature synthesized MOF-177. The MOF-177 sample was characterized by various techniques like Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray, powder X-ray diffraction, nuclear magnetic resonance and CHNS elemental analysis. The MOF-177 electrode was prepared and electrochemical performance was carried out to explore the electrical activity of MOF-177. Cyclic voltammetry studies were performed in 0.05 M $$\hbox {K}_{4}\hbox {Fe(CN)}_{6}$$ solution and electrochemical sensing experiments were performed in 0.05 M $$\hbox {H}_{2}\hbox {SO}_{4}$$ and pH 7 buffer solution. A significantly increased electron transfer property has been observed and it has been explored for the electrochemical detection of heavy metal ions. The MOF-177 / cp electrode has shown excellent sensitivity towards toxic heavy metal ions such as $$\hbox {Pb}^{2+}$$ and $$\hbox {Cd}^{2+}$$ at the limit of detection of 0.004 and 0.03 $$\upmu \hbox {M}$$ , respectively.