Dihydrogen orthophosphate on phosphomolybdic acid/(Ln-MOFs) modified glassy carbon electrode electrochemical reduction process

Lanthanide metal–organic framework Ln-MOFs(Ln = Sm, Dy, Dy/Sm) were synthesized by hydrothermal method at 100 °C for 12 h using lanthanide metals (Ln = Sm, Dy, Dy/Sm) as metal ion centers and 1,3,5-benzotrioic acid (H 3 BTC) as ligands. The structural characteristics of Ln(BTC)(H 2 O)·(DMF) were characterized by X-ray Diffraction(XRD), Fourier Transform Infrared Spectroscopy(FT-IR) and Thermogravimetric Analysis(TGA). Scanning electron microscopy showed that the samples showed rod-like morphology, and the fluorescence spectra showed 478 nm and 573 nm corresponding to the characteristic transitions of 4 F 9/2 → 6 H 15/2 (blue light) and 4 F 9/2 → 6 H 13/2 (yellow light) of Dy 3+ , respectively, while orange light at 600 nm and red light at 646 nm corresponded to the characteristic transitions of 4 G 5/2 → 6 H 7/2 and 4 G 5/2 → 6 H 9/2 of Sm 3+ , demonstrating that the double-doped lanthanide metal ions MOF were successfully synthesized. H 7 (P(Mo 2 O 7 ) 6 )/(Dy/Sm-MOF) was used as a sensor for the determination of H 2 PO 4 − , the results of performance evaluation showed that the electrochemical sensor showed a linear relationship between 0.01 and 0.17 mM for H 2 PO 4 − , with a detection limit of 0.005 mM/L, good stability and reproducibility, which opened up a new way for the detection of orthophosphate dihydrogen.