Total conductivity, Seebeck coefficient and ion transference number measurements in atmospheres
4-probe DC conductivity measurements in controlled atmospheres, combined with Seebeck coefficient determination. The measurements can be performed in the temperature range 650 - 1000 îÑ at oxygen partial pressures from 10-20 up to 1 atm.
Impedance spectroscopy and 4-probe DC conductivity measurements at 20 - 1100 î Ñ in flowing dried or humidified gases: air, O2, Ar, 7% H2 – Ar, CO2 or their mixtures.
Ion transference number determination by modified electromotive force (EMF) and faradaic efficviency (FE) methods, taking electrode polation into account.
The oxygen and water vapor partial pressures in the gas flows are continuously controlled by sensors. When necessary, gas chromatographic analysis can also be used.
Long-term stability tests of selected materials and complex electrochemical cells.
Standard measuring ranges:
Total electrical conductivity: from 10-8 to 104 S/cm,
Grain-boundary contributions to electrical resistivity: 0.5 to 100%,
Seebeck coefficient: 1 to 800 µV/K,
Oxygen ion transference numbers: 10-4 to 0.999,
Proton transference numbers: 0.05 to 0.99,
Electrolytic domain boundaries: 10-20 to 0.8 atm O2.