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The paper reports the data on the sensing properties of xCaO-(100-x)ZrO2 (CSZ, x=9, 12 and 15 mol.%) and 8Y2O3-92ZrO2 (YSZ) solid electrolytes, manufactured from nanosized lowagglomerated powder. Stabilized zirconia solid electrolytes (SE) were synthesized via the original co-precipitation technique and annealing at 1823K in air for 3 hours. Phase composition and conductivity of obtained ceramics was investigated via XRD and impedance spectroscopy techniques. Electromotive force (EMF) response on O2 partial pressure was obtained at 966K for sensors with stabilized zirconia membranes. The data obtained was compared with Nernst equation. The impact of the precursor powder synthesis technique on electrical and sensing properties was discussed. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells are currently constructed using a yttria stabilised zirconia electrolyte membrane. However, zirconia has a number of disadvantages associated with its use, such as the high operational temperatures required for it to exhibit acceptable levels of ionic conductivity. Alternative ceramics such as doped cerium oxide show promise as electrolytes capable of operating at reduced temperatures, but introduce additional problems such as electronic conduction and inferior mechanical properties. This paper describes the manufacture and characterisation of a number of prototype electrolytes consisting of a mixture of yttria stabilised zirconia and gadolinium doped ceria. Traditional ceramic processing techniques were used to produce the samples, which were then examined using dilatometry, impedance spectroscopy and X-ray diffraction. Results show a lowering of the ionic conductivity of zirconia with the addition of doped ceria. X-ray diffraction patterns obtained from the samples suggested that this effect could be attributed to the formation of a solid solution of ceria in zirconia. [ABSTRACT FROM AUTHOR]