Assemble-Electrodeposited Ultrathin Conducting Poly(Azure A) at a Carbon Nanotube-Modified Glassy Carbon Electrode, and its Electrocatalytic Properties to the Reduction of Nitrite

Abstract

A new type of ultrathin conducting polymer/carbon nanotubes (UCP/CNTs) nanomaterials with high catalytic surface area was proposed in this work. The electrode covered with an ultrathin layer of poly(azure A)/carbon nanotubes nanomaterials was fabricated by two steps: firstly, the single-wall carbon nanotubes (SCNTs) modified glassy carbon (GC) electrode was immersed in an azure A solution to assemble a thin azure A monomer film. Secondly, the assembled AA was electropolymerized in a phosphate buffer solution by cyclic voltammetry (CV). The electrocatalytic activity of the obtained ultrathin conducting poly(azure A)/carbon nanotubes (UCPAA/CNTs) nanomaterials was tested using sodium nitrite. The results showed thus prepared electrode exhibited excellent electrocatalytic behavior to the reduction of nitrite and facilitates the detection of nitrite at an applied reduction peak potential of 0.1 V. A linear range from 3.0 µM to 4.5 mM for the detection of sodium nitrite has been observed with fast response (within 3 s) and a detection limit of 1.0 µM based on a signal-to-noise ratio of 3.