A nitrite electrochemical sensor based on electrodeposition of zirconium dioxide nanoparticles on carbon nanotubes modified electrode

A nitrite electrochemical sensor based on electrodeposition of zirconium dioxide nanoparticles on carbon nanotubes (MWCNTs) modified gold electrode was proposed. Scanning electron microscope and energy-dispersive X-ray spectroscopy analysis were used for the characterization of ZrO2/MWCNTs composite. Electrochemical experiments showed that the proposed ZrO2/MWCNTs composite-modified electrode exhibited excellent electrocatalytic properties for nitrite. The potential utility of electrodes constructed was demonstrated by applying them to the analytical determination of nitrite concentration. An optimized limit of detection of 0.3 mu M was obtained at a signal-to-noise ratio of three and with a fast response time (within 3 s). Additionally, the ZrO2/MWCNTs/Au electrodes exhibited a wide linear range from 0.5 to 1,115.5 mu M and high sensitivity. The simple fabrication, high stability, and low cost of the modified electrode are the promising features of the proposed sensor.