A novel electrochemical sensor based on Ag nanoparticles decorated multi-walled carbon nanotubes for applied determination of nitrite

Ag nanoparticles decorated multi-walled carbon nanotubes (MWCNTs) composite was prepared by a simple electrochemical deposition approach. Transmission electron microscopy (TEM) and Energy dispersive spectroscopy (EDS) were employed to characterize the morphology and composition of the composite. The results showed that Ag nanoparticles with an average size approximately 20 nm were uniformly deposited on the MWCNTs surface. The electrochemical performance of the suggested sensor was investigated via differential pulse voltammetry (DPV) and chronoamperometry. Under optimum conditions, the AgNPs/MWCNTs/GCE displayed a rapid current response to nitrite, with the anodic peak current varying linearly with nitrite concentration in the range of 1 μM–100 μM ( R  = 0.9989) accompanying a low detection limit of 0.095 μM. The long-term stability and good reproducibility were also achieved on the proposed sensor. The determination of nitrite in tap water was studied and showed desirable recovery rate, signifying its possibility for practical application.