The effect of catalyst film thickness on the electrochemical promotion of ethylene oxidation on Pt
The effect of catalyst film thickness on the magnitude of the effect of electrochemical promotion of catalysis (EPOC or NEMCA effect) was investigated for the model catalytic reaction of C2H4 oxidation on porous Pt paste catalyst-electrodes deposited on YSZ. It was found that the catalytic rate enhancement ρ is up to 400 for thinner (0.2 μm) Pt films (40,000% rate enhancement) and gradually decreases to 50 for thicker (1 μm) films. The results are in good qualitative agreement with model predictions describing the diffusion and reaction of the backspillover O2− species which causes electrochemical promotion.
Keywordselectrochemical promotion NEMCA effect porous film thickness effect ethylene oxidation promotional rules
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