Autor: |
Ramos, Guadalupe, Vazquez, Gerardo, David, Manuel, Collins, Virginia M., Solorza, Omar |
Zdroj: |
ECS Transactions; November 2009, Vol. 20 Issue: 1 p407-412, 6p |
Abstrakt: |
The catalytic activity of carbon supported PdNi and Pd0.5Ni0.45Se0.05 materials for the oxygen reduction reaction (ORR) in acid media at 25{degree sign}C was studied. The electrocatalysts were synthesized by a chemical from metallic precursors with NaBH4. Thermal treatment in hydrogen atmosphere was performed in a stainless steel reactor, to improve their catalytic properties. The X-Ray diffraction pattern showed an enhancement of the crystallinity as well as a grown of the crystallite size in comparison to those without heat treatment. Displacements of diffraction peaks towards more positive 2th values were observed and associated to the incorporation of the elements inside a crystalline structure.The catalytic activity was studied by electrochemical hydrodynamic techniques; the mass transfer corrected Tafel plots showed a decreasing in ~50 mV in the overpotential of Pd0.5Ni0.45Se0.05 to reach the same PdNi current density. There is not a significant enhancement of the Pd0.5Ni0.45Se0.05 catalyst associated to the formation of new inactive-ORR phases. |
Databáze: |
Supplemental Index |
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