Abstract
The effect of sodium-modification on the catalyst and electrocatalytic properties of a platinum catalyst supported on a YSZ solid electrolyte was studied. Increasing the sodium coverage on the catalyst surface appears to block some of the three-phase boundary (tpb) sites and reduces the rate of the charge transfer reaction. The promotion of the platinum surface reaction (ethylene oxidation) seems to a first approximation to be a function of the rate of oxygen supply or removal to or from the surface irrespective of whether this is contaminated by sodium or not (samples with sodium contamination require a higher overpotential to achieve the same current density as a clean sample because of poisoning in the tpb). At high negative polarisations (oxygen removed from the surface) the sodium contaminated samples show a significant increase in rate, possibly due to the decomposition of e.g. sodium hydroxides and carbonates.
Original language | English |
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Pages (from-to) | 386-389 |
Number of pages | 4 |
Journal | Solid State Ionics |
Volume | 225 |
DOIs | |
Publication status | Published - 04 Oct 2012 |
Keywords
- Cyclic voltammetry
- EPOC
- Ethylene oxidation
- Na species
- Oxygen charge transfer
- Pt
- YSZ
ASJC Scopus subject areas
- General Materials Science
- Condensed Matter Physics
- General Chemistry