Ni-Fe Alloy Coatings Prepared via Jet Electrodeposition for the Optimization of the Electrochemical Detection Performance of Laser-Induced Graphene for Pb(II)

Heavy metal pollution in water, particularly Pb ion pollution, has seriously threatened human life and health. Therefore, the manufacture of efficient and sensitive heavy metal ion detection materials is essential. The objective of this study was to improve the electrochemical detection performance of laser-induced graphene (LIG) for Pb(II). Considering the excellent ion affinity and high activity of transition metals, Ni-Fe alloy coatings were prepared on the surface of LIG through jet electrodeposition. The prepared LIG and Ni-Fe/LIG were qualitatively analyzed through Raman spectrometry, X-ray diffraction analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The surface micromorphologies, charge transfer capabilities, and electrochemically active surface areas of LIG and Ni-Fe/LIG were characterized. The detection range and limit of detection (LOD) of Pb(II) for LIG and Ni-Fe /LIG as electrochemical sensors were analyzed. Results showed that compared with LIG, Ni-Fe/LIG had more surface active sites, a higher charge transfer capability, and a larger electrochemically active surface area that reached 0.828 cm(2). Ni-Fe/LIG had a detection range of 20-1200 & mu;g/L and an LOD of as low as 0.771 & mu;g/L. Ni-Fe/LIG demonstrated a better electrochemical detection performance for Pb(II) than LIG when used as an electrochemical sensor.