Highly Sensitive Amperometric Sensor Based on Gold Nanoparticles Polyaniline Electrochemically Reduced Graphene Oxide Nanocomposite For Detection of Nitric Oxide

A sensitive electrochemical sensor was fabricated for selective detection of nitric oxide (no) based on electrochemically reduced graphene (ergo)-polyaniline (pani)-gold nanoparticles (aunps) nanocomposite. it was coated on a gold (au) electrode through stepwise electrodeposition to form aunps-pani-ergo/au electrode. the aunps-pani-rgo nanocomposite was characterized by field emission scanning electron microscopy (fesem) and uv-vis. electrochemical behavior of modified electrode was analyzed by cyclic voltammetry (cv) and chronoamperometry (ca) techniques. cvs of aunps-pani-ergo/au, pani-ergo/au and ergo/au electrodes showed that conductivity of aunps-pani-ergo/au was higher than others. nafion was used to improve selectivity of modified electrode. nafion/aunps-pani-ergo/au electrode represented favorable electrochemical and electrocatalytic behavior towards no oxidation. the resultant electrode exhibited a high sensitivity of 0.113 μa/μm over a wide linear range from 0.8 × 10^−6 to 86 × 10^−6 m with a low detection limit of 2.5 × 10^−7 m (s/n=3). in addition, the sensor had excellent stability, as well as reproducibility and selectivity, which makes it possible to detect no quickly and accurately.