High Electrocatalytic Activity of the Pt-Based Catalyst Supported on Carbon Prepared Using a Plasma Torch and Natural Gas

Physicochemical and electrochemical characterisations of Pt-based electrocatalysts supported on carbon (Vulcan® XC72, C1 and carbon produced using a plasma torch from natural gas vehicles, C2) toward ethanol electrooxidation were investigated. The Pt/C1 and Pt/C2 electrocatalysts were prepared by thermal decomposition of polymeric precursors at 350 ° C. The electrochemical and physicochemical characterisations of the electrocatalysts were performed by means of X-ray diffraction (XRD), Raman scattering, cyclic voltammetry and chronoamperometry tests. The XRD results show that the Pt-based electrocatalysts present platinum metallic which is face-centered cubic structure. The results indicate that the Pt/C1 electrocatalyst has a smaller particle size (10.1 – 6.9) compared with the Pt/C2 electrocatalyst; however, the Pt/C2 particle sizes are similar (12.8 – 10.4 nm) and almost independent of the reflection planes, which suggests that the Pt crystallites grow with a radial shape. Raman results showed that all the materials are composed of randomly oriented structural units varying from 50 to 80 Å in size. Cyclic voltammetry and chronoamperometry data obtained in this study indicate that the deposition of Pt on carbon plasma increases its electrocatalytic activity toward ethanol oxidation.

Acknowledgments

FAPES, CAPES, FINEP, PETROBRAS, LMC and CNPq.