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Licensed Unlicensed Requires Authentication Published by De Gruyter December 30, 2021

The Influence of Al or B on the Thermoelectric Power of Pt/Pt–Rh Thermocouples

Horst Brodowsky, Martin Ketzner and Christian Krey

Abstract

Impurities of Al or B exert a strong influence on the absolute thermoelectric power of Pt and Pt–Rh alloys.

There is a change to less negative values in pure Pt and to more negative values in alloys of more than about 6 wt.% Rh. Consequently, the thermoelectric voltage of thermocouples with one leg of pure Pt is much more sensitive to Al or B impurities than thermocouples made of two different Pt-Rh alloys. The dependence of the absolute thermoelectric power on the valence electron concentration of the alloys studied is correlated to the derivative of the molar susceptibility vs valence electron concentration, as called for by various models connecting thermoelectric phenomena to the band structure of the materials.


H. Brodowsky,[1)] M. Ketzner, Ch. Krey Institut für Physikalische Chemie der Universität Kiel Olshausenstr. 40 D-24098 Kiel, Germany

  1. We wish to thank Dr. H. Pausch (Institut für Anorganische Chemie der Universität Kiel) for support with the magnetic measurements. We also wish to thank the Degussa AG for providing Pt and Pt–Rh thermocouples free of charge.

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Received: 1998-01-08
Published Online: 2021-12-30

© 1998 Carl Hanser Verlag, München