A high-activity Fe-based MOFs fabricated through ultrasound strategy for electrochemical sensor of heavy metal ions and dopamine

Spindle-shaped NH 2 -MIL-101(Fe) has been fabricated through the ultrasound-assisted synthesis method and then characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscope (SEM), High resolution transmission electron microscope (HRTEM), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET) analyses. The sample shows a high-performance electrochemical sensor for heavy metal ions (Pb(II), Cu(II) and Hg(II)) and dopamine. The as-prepared NH 2 -MIL-101(Fe)/GCE electrode exhibited detection limits of 12.0 nM, 8.53 nM, and 18.0 nM for Pb(II), Cu(II) and Hg(II), respectively, and with good stability and reproducibility. The NH 2 -MIL-101(Fe)/CPE electrode for dopamine detection showed a wide linear range of 0.3 to 450 μM with a detection limit of 0.025 μM, and also demonstrating excellent anti-interference properties and stability. This study provides a new strategy through simple ultrasound preparation for the highly sensitive electrochemical sensor detection of heavy metal ions and organic compounds.