▎ 摘　　要

The effect of annealing temperature variance on magnesium ferrites (MgFe2O4) later anchored on reduced graphene oxide (rGO) forming hybrid nanocomposite is demonstrated and its electrochemical performance investigated by using a screen-printed carbon paste electrode (SPCE) for detection of the environmental hazardous phenolic compound 4-cyanophenol (4-CY). The MgFe2O4 (MFO-600 degrees C) displayed an enhanced charge transfer ratio with high conductivity and electrocatalytic activity. To confirm the structural and morphological parameters of the rGO-MFO-2 hybrid micro/nanocomposite, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron microscopy (XPS), and field-emission electron microscopy (FE-EM) with EDX mapping have been utilized. The rGO/MFO-2/SPCE electrode displayed high catalytic performance in detecting 4-CY with good sensitivity of 6.836 mu A mu M-1 cm(-2) in a working range 0.001 to 700 mu M with a limit of detection of 0.0012 mu M by using differential pulse voltammetry (DPV). This is achieved for the active interaction between rGO and MFO-2 active surface site areas resulting in good electrochemical activity and high electron transfer rate. Moreover, 4-CY detection has been performed in the presence of various interferents and through real-time analysis in samples like tap water, industrial river water, and fish which resulted in admirable recovery.