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 mu M) with a limit of detection (LOD) of 0.09 mu M (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.