Core-shell Au/Ag nanoparticles embedded in silicate sol-gel network for sensor application towards hydrogen peroxide

The electrocatalytic activity of core-shell Au100-x Ag (x) ((x) = 15, 27, 46, and 60) bimetallic nanoparticles embedded in methyl functionalized silicate MTMOS network towards the reduction of hydrogen peroxide was investigated by using cyclic voltammetry and chronoamperometric techniques. Core-shell Au/Ag bimetallic nanoparticles were characterized by absorption spectra and HRTEM. The MTMOS silicate sol-gel embedded Au73Ag27 core-shell nanoparticles modified electrode showed better synergistic electrocatalytic effect towards the reduction of hydrogen peroxide when compared to monometal MTMOS-Au-nps and MTMOS-Ag-nps modified electrodes. These modified electrodes were studied without immobilizing any enzyme in the MTMOS sol-gel matrix. The present study highlights the influence of molar composition of Ag nanoparticles in the Au/Ag bimetallic composition towards the electrocatalytic reduction and sensing of hydrogen peroxide in comparison to monometal Au and Ag nanoparticles.