Fabrication of novel electrochemical sensor based on bimetallic Ce-Ni-MOF for sensitive detection of bisphenol A

In this paper, a novel bimetallic Ce-Ni metal-organic frameworks (Ce-Ni-MOF) are synthesized by hydrothermal reaction, using 1,3,5-benzenetricarboxylic acid as a ligand. In particular, the bimetallic Ce-Ni-MOF with the largest specific surface area and catalytic sites was synthesized when the molar ratio of Ce³⁺ to Ni²⁺ was 3:7. Bimetallic Ce-Ni-MOF is added to the traditional conductive material of multiwall carbon nanotubes (MWCNTs) to play their synergistic effect, improve the conductivity, specific surface area, and catalytic site of the MWCNTs. A novel bisphenol A (BPA) sensor was successfully prepared by a self-assembled multilayer strategy of Ce-Ni-MOF/MWCNTs modified glassy carbon electrodes (GCE). Field emission scanning electron microscopy, powder X-ray diffraction, and transmission electron microscope were carried out to characterize the Ce-Ni-MOF/MWCNTs. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used as a sensitive analytical method for the determination of BPA, and a wider linear dynamic range of BPA determination in 0.1 μmol·L^-1 to 100 μmol·L^-1 with a detection limit of 7.8 nmol·L^-1 (S/N = 3). The proposed method was applied to measure the content of BPA in different brands of drinking water with satisfying recovery from 97.4 to 102.4%. Graphical abstract.