Kinetics of oxygen reduction reaction on nanosized Pd electrocatalyst in acid media
| Autor: | Omar Solorza-Feria, S. Citalán-Cigarroa, J.J. Salvador-Pascual |
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| Rok vydání: | 2007 |
| Předmět: |
Renewable Energy
Sustainability and the Environment Chemistry Enthalpy Inorganic chemistry Analytical chemistry Energy Engineering and Power Technology chemistry.chemical_element Electrolyte Electrocatalyst Electrochemistry Catalysis Electrical and Electronic Engineering Physical and Theoretical Chemistry Cyclic voltammetry Rotating disk electrode Palladium |
| Zdroj: | Journal of Power Sources. 172:229-234 |
| ISSN: | 0378-7753 |
| DOI: | 10.1016/j.jpowsour.2007.05.093 |
| Popis: | Palladium electrocatalyst powder was prepared through PdCl2 reduction with NaBH4 in a THF solution at 0 °C. Characterization of the palladium phases, morphology and topography was performed by XRD, SEM, and AFM. Results from the X-ray diffraction (XRD) study showed evidence of nanocrystalline fcc hexagonal palladium formation with 4 nm in an average size. Electrocatalyst activity for the oxygen reduction reaction, ORR, was examined using cyclic voltammetry through rotating-disk electrode measurements in a 0.5 M H2SO4 electrolyte. Kinetic results suggest that the initial electron transfer is the rate-determining step. An apparent enthalpy of activation ΔH°# = 89.5 ± 0.5 kJ mol−1 was calculated from electrochemical results at different temperatures. Based on current densities and the enthalpy of activation results, the nanosized Pd catalysts are significantly less active for the ORR than Pt and Ru electrocatalysts. |
| Databáze: | OpenAIRE |
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