Nickel-metal organic framework/MWCNT composite electrode for non-enzymatic urea detection

A porous composite catalyst based on nickel-metal organic framework (Ni-MOF) and multiwalled carbon nanotubes (MWCNTs) was synthesized for non-enzymatic urea detection. The Ni-MOF was characterized by Fourier transform infrared spectroscopy, X-ray photo electron spectroscopy and X-ray diffraction techniques. The morphology and the structure of the Ni-MOF were studied using scanning electron microscopy and transmission electron microscopy. The Ni-MOF/MWCNTs coated indium tin oxide glass was used as a novel electrochemical sensor for urea detection. The Ni-MOF/MWCNT electrode showed a very high sensitivity of 685 μAmM−1cm−2, low detection limit of 3 μM and a response time of 10 s. Moreover, the sensor showed remarkable stability with no loss in activity after 30 days of storage under ambient conditions. Overall, the novel hybrid inorganic–organic material showed notable potential for designing of micro-scale point of care diagnostic devices for urea sensing applications.