Microstructure and electrical conductivity of yttria-stabilized zirconia with lithium addition

Abstract

Yttria-stabilized zirconia is a singular polycrystaline ceramic with a range of technological applications. The combination of its physical properties is responsible for application as solid electrolytes in solid oxide fuel cells. High densification is required for this and other applications. The sintering of this solid electrolyte is still a matter of investigation. To reduce the sintering temperature, the introduction of additives is an effective approach. In this work, the effects of lithium addition on microstructure and electrical conductivity of 8 mol% yttria-stabilized zirconia was studied by scanning electron microscopy and impedance spectroscopy, respectively. Cylindrical pellets were prepared by pressing, followed by sintering at 1200ºC without and with 1 and 2 mol% lithium (metal basis). As precursor materials both lithium carbonate and lithium fluoride were used. The main microstructure features were correlated with the results of electrical conductivity.