Estudo da eletrooxidação de glicerol sobre eletrocatalisadores ternários

Abstract

In this work, we investigated the electrochemical oxidation of glycerol on nanoparticles of Pt-Co-Ni/C in three different metal ratios, prepared by reduction method by ethylene glycol. Ternary, Pt75Co0,9Ni24,1/C, Pt75Co12,5Ni12,5/C, Pt75Co24,1Ni0,9/C and binary Pt75Co25/C and Pt75Ni25/C catalysts were prepared and characterized by X Ray Diffraction, Transmission Electronic Microscopy and Scan Electronic Microscopy. The XRD analysis allowed the calculation of concentration particle diameters and showed changes in the lattice parameter values and unit cell volume, indicating the insertion of the metals Ni and/or Co in crystalline structure of Pt. Through TEM analysis it was observed good dispersion of metals on carbon and particle sizes were determinate between 2-10 nm. The scanning micrographs showed morphological specific characteristic of such materials that can contribute to the glycerol oxidation. The electrochemical analyzes suggest that the synthesized materials are active and stable for glycerol oxidation in an alkaline medium. Cyclic voltammograms indicated that Pt75Co12,5Ni12,5/C exceed the others. The chronoamperometry and Mass Spectroscopy were fundamental for the identification of some products formed from the oxidation of glycerol in the studied conditions, as glyceric acid and hydroxipiruvic acid.