High Temperature Reference Electrodes





The question of high temperature reference electrodes seems to come up often and in a wide range of applications.  Here are a couple of extreme examples from the molten salt community.

Ag / AgCl - This is not your typical aqueous reference electrode, but rather an "electrode of the first kind".  It consists of a silver wire immersed in molten silver chloride (ref 1) ! The potential is controlled by the Ag(I)/Ag couple. An asbestos wick could be used to form a liquid junction between the AgCl and your melt.

Zn / Zn(II) - This reference electrode was used (ref 2) in a molten salt application in a ZnCl2, 2NaCl melt at 450C.  Molten zinc, in contact with the ZnCl2 / 2NaCl melt was used as a reference electrode.  A tungsten wire was used as a connection to the molten zinc. The potential is controlled by the Zn(II)/Zn(liq) couple. Because the solvent/electrolyte makes up one half of the couple, this reference electrode is not plagued by liquid junction potential uncertainties!

More about Reference ElectrodesMore About Reference Electrodes



 How useful was this information? Give us your FEEDBACK !

(1) "Reference Electrodes. Theory and Practice", DJG Ives & GJ Janz, eds., Academic Press, NY (1961).
(2) "Electrochemical study of the properties of iron ions in ZnCl2 + 2NaCl melt at 450C", Y Castrillejo, AM Martinez, M Vega, E Barrado, G Picard, J Electroanal Chem, 397(1995) 139.




Valid HTML 4.0!© Copyright 2002-2012 Research Solutions & Resources.
All rights reserved.