The electrochemical promotion of ethylene oxidation at a Pt/YSZ catalyst
| Autor: | Liz M. Rösken, Ronald Imbihl, Arafat Toghan |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Working electrode
Materials science Surface Properties Inorganic chemistry chemistry.chemical_element Water Carbon Dioxide Ethylenes Heterogeneous catalysis Electrochemistry Atomic and Molecular Physics and Optics Catalysis Oxygen Photoemission electron microscopy Adsorption chemistry Yttrium Zirconium Physical and Theoretical Chemistry Platinum Oxidation-Reduction Yttria-stabilized zirconia |
| Zdroj: | Chemphyschem : a European journal of chemical physics and physical chemistry. 11(7) |
| ISSN: | 1439-7641 |
| Popis: | The electrochemical promotion of the C(2)H(4)+O(2) reaction to form CO(2) and H(2)O is studied in the 10(-5) and 10(-4) mbar range with a Pt catalyst interfaced as working electrode to yttrium-stabilized zirconia (YSZ). Photoemission electron microscopy (PEEM) was used as spatially resolving method. Under open-circuit conditions, that is, without an external voltage applied, the CO(2) production exhibits a pronounced hysteresis upon cyclic variation of p(C(2)H(4)). The hysteresis is attributed to the build-up of a carbonaceous CH(x) layer inhibiting O(2) adsorption and hence poisoning the reaction. It is shown that the application of a positive potential of 1 V triggers a transition from the unreactive branch of the reaction to an active branch. The large non-Faradayicity reported in the literature for this reaction system is explained as an ignition effect caused by the partial removal of the inhibiting carbonaceaous layer. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text