Silver nanoparticles embedded three dimensional silicate sol-gel matrix modified electrode for nitrite sensor application

Abstract

A simple amperometric sensor was fabricated by using silver nanoparticles (Ag_nps) embedded three dimensional silicate sol-gel (SG) matrix (SG-Ag_nps). The silver nanoparticles stabilised by SH functionalised 3-D silicate sol-gel network was coated on the glassy carbon electrode and used for the determination of nitrite ion in 0.1 M PBS (pH 7.2). The prepared silver nanoparticles-silicate sol-gel (SG-Ag_nps) modified electrode was characterised by UV-visible absorption spectroscopy, scanning electron microscopy (SEM) and electrochemical method. The electrochemical behaviour of SG-Ag_nps modified electrode was studied by using potassium ferricyanide as a redox marker to probe the tunable kinetic barrier of the dispersed silver nanoparticles in silicate sol-gel matrix. The SG-Ag_nps film was used as nanomaterials comprised electrochemical device for direct electrocatalysis and amperometric sensing of nitrite ion. The silver nanoparticles embedded silicate sol-gel film showed good stability and sensitivity with an experimental amperometric detection limit of 4 M. The fabrication of SG-Ag_nps modified electrode was very simple and it showed fast amperometric response and reproducible results for nitrite sensing.