Ionics

, Volume 2, Issue 3–4, pp 282–288 | Cite as

Non-Faradaic electrochemical modification of the catalytic activity of Pt using a CaZr0.9In0.1O3-α proton conductor

  • M. Makri
  • A. Buekenhoudt
  • J. Luyten
  • C. G. Vayenas
Article

Abstract

The effect of non-Faradaic electrochemical modification of catalytic activity (NEMCA) was investigated for the case of C2H4 oxidation on a Pt polycrystalline catalyst film also acting as a working electrode in a galvanic cell of the type:
$$C_2 H_4 ,O_2 ,CO_2 ,H_2 O,Pt|CaZr_{0.9} In_{0.1} O_{3 - \alpha } |Au,C_2 H_4 , O_2 ,CO_2 ,H_2 O$$

In addition to proton conduction, CaZr0.9In0.1O3-α is known to exhibit oxygen and hole conduction. Proton conduction predominates over the temperature range, 380 to 460 °C, of the present investigation.

It was found that negative current application, i.e. proton supply to the Pt catalyst film causes up to 500% reversible enhancement to the rate of C2H4 oxidation. The catalytic rate increase is up to 20,000 higher than the rate, -I/F, of proton supply to the catalyst. The observed phenomena are discussed within the framework of previous electrochemical promotion (NEMCA) studies.

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Copyright information

© IfI - Institute for Ionics 1996

Authors and Affiliations

  • M. Makri
    • 1
  • A. Buekenhoudt
    • 2
  • J. Luyten
    • 2
  • C. G. Vayenas
    • 1
  1. 1.Dept. of Chemical EngineeringUniversity of PatrasPatrasGreece
  2. 2.Materials and Energy Department Boeretang 200VitoMolBelgium

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