Electrochemical Determination of Nitrite Using a Gold Nanoparticles-modified Glassy Carbon Electrode Prepared by the Seed-mediated Growth Technique

Seed-mediated growth of gold nanoparticles on glassy carbon (GC) surfaces was developed. The field emission scanning electron microscopy (FE-SEM) and electrochemical characterization confirmed the effective attachment of gold nanoparticles on GC surface with such a wet-chemical method. The as-prepared gold nanoparticles attached glassy carbon electrode (Au/GCE) presented excellent catalytic ability toward the oxidation of nitrite. Compared with bare GCE and planar gold electrode, the Au/GCE obviously decreased the overpotential of nitrite oxidation and improved the peak current. The catalytic current was found to be linearly proportional to the nitrite concentration in the range of 1 × 10-5 - 5 × 10-3 M, with a detection limit of 2.4 × 10-6 M. The Au/GCE was successfully applied to the electrochemical determination of nitrite in a real wastewater sample, showing excellent stability and anti-interference ability