Bimetallic Pt-Ru Nanoparticle Catalyst for Hydrogen Peroxide Detection

A bimetallic Pt-Ru nanoparticle catalyst was prepared and characterized for the enhancement of hydrogen peroxide (H2O2) detection in biosensing applications. The particles were synthesized via sodium borohydride reduction, with low heat treatment, and characterized by TEM and HRTEM. The chemical composition analyses were performed by EDX. The bimetallic particle diameters ranged from 2 to 12 nm, with an average of 4.5 nm. The Pt-Ru catalyst exhibited an improved performance at low overpotential (+0.2V versus Ag/AgCl reference electrode) in H2O2 detection, suggesting a sensitivity value of 78.95 mu A center dot mM-1 (or 402.1 mu A center dot mM-1 center dot cm(-2)) which was 30% higher than that for the single Pt catalyst. The major contribution of this enhancement comes from the stronger oxygen adsorption on Ru metal. The Pt-Ru catalyst also showed a more stable signal at the high overpotential (+0.4V versus Ag/AgCl), providing better accuracy in the detection of H2O2.