Electrocatalytic Properties Of Metal Nanoparticles Supported On Carbon Nanostructure Materials

The fabrication and application of sensitive electrodes based on metal nanoparticles supported on carbon based materials is of practical importance when developing simple methods for quick detection of trace quantities of analytes. These sensors exhibit a wide range of advantages such as simplicity, relatively fast response, low cost, wide linear dynamic range and ease of preparation and procedures when compared to conventional methods. As such, the electrochemical and electrocatalytic behavior of the metal nanoparticles supported on carbon nanostructures remain an area for further exploration.Briefly, in chapter two, a novel glucose biosensor was developed based on platinum nanoparticles decorated hollow carbon spheres (Pt/HCSs) deposited on glassy carbon electrode (GCE) and then glucose oxidase (GOx) was immobilized on the modified electrode with the help of Nafion. Glucose was detected via the electrochemical detection of hydrogen peroxide (H2O2), a by-product of the enzymatic reaction. This glucose biosensor showed good electrocatalytic performance in terms of high sensitivity (4.1028μAmM-1), low detection limit (1.8μM), fast response time<3s, wide linear range (0.04-8.62mM) and the Michaelis-Menten constant (Km) value of10.94mM.And finally, in chapter three, platinum nanoparticles/thermally reduced graphenes (Pt-TRGs) composites were successfully prepared using TRGs as supports. The structure and morphology of the resulting composites were characterized by transmission electron microscopy (TEM). The results showed that Pt nanoparticles with size ranging from1.3to6.0nm were well dispersed on the surface of TRGs and with a mean size of3.4nm. The electrocatalytic activity of Pt-TRGs composites for hydrazine was investigated on the modified glassy carbon electrode by cyclic voltammetry and chronoamperometry.The resulting Pt-TRGs composites showed excellent electrocatalytic activity. This may be due to the small particle size and good dispersion of Pt nanoparticles as well as the unique properties of TRGs supports.