Fabrication of a novel electrochemical sensor based on MnFe₂O₄/graphene modified glassy carbon electrode for the sensitive detection of bisphenol A

Manganese ferrite (MnFe₂O₄) has the advantages of simple preparation, high resistivity, and high crystal symmetry. Herein, we have developed an electrochemical sensor utilizing graphene and MnFe₂O₄ nanocomposites modified glassy carbon electrode (GCE), which is very efficient and sensitive to detect bisphenol A (BPA). MnFe₂O₄/graphene (GR) was synthesized by immobilizing the MnFe₂O₄ microspheres on the graphene nanosheets via a simple one-pot solvothermal method. The morphology and structure of the MnFe₂O₄/GR nanocomposite have been characterized through scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). In addition, electrochemical properties of the modified materials are comparably explored by means of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). Under the optimal conditions, the proposed electrochemical sensor for the detection of BPA has a linear range of 0.8–400 µmol/L and a detection limit of 0.0235 µmol/L (S/N=3) with high sensitivity, good selectivity and high stability. In addition, the proposed sensor was used to measure the content of BPA in real water samples with a recovery rate of 97.94%–104.56%. At present, the synthesis of MnFe₂O₄/GR provides more opportunities for the electrochemical detection of BPA in practical applications.