Determination of nitrite with a nano-gold modified glassy carbon electrode by cyclic voltammetry

The fabrication and electrochemical characteristics of nano-gold modified glassy carbon (NG/GC) electrode were investigated. The modified electrode showed an obvious electrocatalytic activity for the oxidation of nitrite at 0.850 V versus the Ag/AgCl electrode in 0.05 mol L-1 H2SO4 solution. Some electrochemical parameters, such as the diffusion coefficient, D, electron transfer number, n, and rate constant, k(s), were calculated. The peak current was proportional to the concentration of nitrite in the range of 5.0 x 10(-6) to 5.0 x 10(-4) mol L-1 for the cyclic voltammogram method with the detection limit of 5.0 x 10(-7) mol L-1. The possible reaction mechanism has also been discussed. The NG/GC electrode has a high stability and can be applied to the determination of nitrite in rain water with simplicity, rapidity, and accurate results.