Two-dimensional BCN nanosheets self-assembled with hematite nanocrystals for sensitively detecting trace toxic Pb(II) ions in natural water.

In the present work, hematite–boron-carbonitride (Fe 2 O 3 –BCN) nanosheets were synthesized by a simple hydrothermal reaction and the following high temperature treatment. The morphology, structure and chemical composition of the as-prepared material were carefully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The Fe 2 O 3 –BCN nanosheets were used to modified on the surface of the glassy carbon electrode to fabricate an electrochemical sensor for lead ions (Pb(II)) via differential pulse anodic stripping voltammetry (DPASV). At the same time, the influence of the modification concentration, solution acidity, deposition potential and deposition time on response peak current of Pb(II) at the Fe 2 O 3 –BCN-based electrochemical sensor was well investigated. Under the optimized conditions, the electrochemical signal and concentration of Pb(II) show two-stage linear relationship in the range of 0.5 – 40 μg/L and 40 –140 μg/L, with a limit of detection (LOD) of 0.129 μg/L. The Fe 2 O 3 –BCN-based electrochemical sensor shows excellent selectivity and anti-interference ability in the anti-interference experiments and actual sample analysis experiments, revealing its broad application in environmental monitoring of Pb(II). Fe 2 O 3 –BCN nanosheet-based electrochemical sensor was fabricated for sensitive determination of trace lead(II) in aqueous environmental samples with detection limit lower than 0.129 μg/L. [Display omitted] • 2D Fe 2 O 3 –BCN composite was easily synthesized via a hydrothermal method. • A noval Fe 2 O 3 –BCN-based electrochemical sensor was fabricated for Pb(II) detection. • The sensor show high sensitivity and good selectivity. • The sensor has a broad linear range with a low LOD of 0.129 μg/L. [ABSTRACT FROM AUTHOR]