Definition and Properties of the Absolute Potential Scale in Solid Electrochemistry

5 DEFINITION AND PROPERTIES OF THE ABSOLUTE POTENTIAL SCALE IN SOLID ELECTROCHEMISTRY 

The same conceptional approach used in aqueous electrochemistry to define absolute electron potentials can be used in solid state electrochemistry. Thus if one chooses as the zero level an electron just outside the solid electrolyte surface, which has been shown14-16 by Trasatti to be the most realistic choice in aqueous electrochemistry, one has  

Experiment (Chapter 5 and Figs. 7.6 to 7.8) has clearly shown that for the gas exposed electrode surfaces in solid state electrochemistry one has  

Thus the absolute electron potential Uw(abs) in solid state electrochemistry can indeed be simply defined by the equation  

The use of the soe scale is more convenient than the she scale in solid state electrochemistry since YSZ (an O2 conductor) is the most commonly used solid electrolyte and the metal/02 (po2 =1 atm)/YSZ (soe) electrode is the most commonly used reference electrode in solid state electrochemistry. 

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