An electrochemical sensor for determination of nitrite based on Au nanoparticles decorated MoS2 nanosheets

An electrochemical sensor for the determination of nitrite was successfully fabricated via electro-depositing Au nanoparticles on a glassy carbon electrode (GCE) modified with MoS2 nanosheets. The morphology and composite of the resulted electrode were characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), respectively. The modified processes of the nanoAu-MoS2/GCE were monitored by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The amperometric current–time (i–t) showed that the developed electrode had excellent response for sodium nitrite under the optimum conditions, and the oxidative current of sodium nitrite was proportionally correlated with its concentration (10–2100 μM) with a limit of detection (LOD) of 0.09 μM (S/N = 3), which can be employed in the determination of nitrite in river and drinking water with the advantages of good reproducibility, anti-interference, long-term stability and satisfactory recovery rate.