Ni nanosheets evenly distributed on MoS2 for selective electrochemical detection of nitrite

A glassy carbon electrode modified by composite material consisting of molybdenum disulfide nanosheets and nickel nanosheets (Ni/MoS2 electrode) was prepared for electrochemical detection of nitrite. Ni/MoS2 was characterized by energy dispersive X-ray spectroscopy, scanning electron microscopy, Raman spectroscopy and X-ray diffraction. Most of MoS2 nanosheets had lateral dimensions less than 150 nm, and the nickel nanosheets were slightly smaller, which were covered on the surface of MoS2 nanosheets evenly. The electrochemical method was used to characterize and study the electrochemical behaviors of Ni/MoS2 and its responses to nitrite. Under the optimized conditions, the prepared Ni/MoS2 electrode showed good detection performances and stability, with a detection range of 5–800 μM, and a detection limit of 2.48 μM (S/N = 3). In addition, by detecting nitrite in tap water, the practical applicability of the electrochemical sensor was verified. [Display omitted] •Nickel nanosheets were covered on the surface of MoS2 nanosheets evenly.•The combination of nickel and MoS2 improved the selectivity and sensitivity of electrochemical detection of nitrite.•The Ni/MoS2 electrode displayed good reproducibility and high stability during nitrite detection.•The Ni/MoS2 electrode successfully used for the detection of nitrite in tap water.