Electrochemical determination of 4-nitrophenol using functionalized graphene oxide/functionalized multi-walled carbon nanotubes hybrid material modified glassy carbon electrode

Herein, a novel carboxylated multi-walled carbon nanotubes-carboxylated graphene oxide coated glassy carbon electrode (f-MWCNTs/f-GO/GCE) was prepared for electrochemical determination of 4-nitropehenol (4-NP). The sensor was characterized using fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), raman spectroscopy, and powder x-ray diffraction (XRD). Electrochmical experiments were performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and amperometry. The resulting f-MWCNTs/f-GO/GCE could be performed for quick, sensitive, and selective determination of 4-NP in the presence of other electroactive compounds. 4-NP was electrochemically detected depending on the reduction of 4-NP at −0.65 V potential using amperometric method. Under the optimum condutions, the sensor showed excellent response to the determination of 4-NP with three linear detection ranges from 0.018 to 700 µM. The sensor exhibited extremely low limit of detection (5.4 nM). Also, the fabricated sensor was used for detection of 4-NP in different water samples.