RT Journal Article T1 Ionic conductivity of nanocrystalline yttria-stabilized zirconia: grain boundary and size effects A1 Durá, O. J. A1 López de la Torre, M. A. A1 Vázquez, L. A1 Chaboy, J. A1 Boada, R. A1 Rivera Calzada, Alberto Carlos A1 Santamaría Sánchez-Barriga, Jacobo A1 León Yebra, Carlos AB We report on the effect of grain size on the ionic conductivity of yttria-stabilized zirconia samples synthesized by ball milling. Complex impedance measurements, as a function of temperature and frequency are performed on 10 mol % yttria-stabilized zirconia nanocrystalline samples with grain sizes ranging from 900 to 17 nm. Bulk ionic conductivity decreases dramatically for grain sizes below 100 nm, although its activation energy is essentially independent of grain size. The results are interpreted in terms of a space-charge layer resulting from segregation of mobile oxygen vacancies to the grain-boundary core. The thickness of this space-charge layer formed at the grain boundaries is on the order of 1 nm for large micron-sized grains but extends up to 7 nm when decreasing the grain size down to 17 nm. This gives rise to oxygen vacancies depletion over a large volume fraction of the grain and consequently to a significant decrease in oxide-ion conductivity. PB American Physical Society SN 1098-0121 YR 2010 FD 2010-05-01 LK https://hdl.handle.net/20.500.14352/44574 UL https://hdl.handle.net/20.500.14352/44574 LA eng NO © 2010 The American Physical Society. We acknowledge financial support by Junta de Comunidades de Castilla-La Mancha through Project No. PAI-05- 013, by CAM under Grant No. S2009/MAT-1756 Phama, by Spanish MICINN through Grants No. MAT2008-06517- C02, No. MAT2008-06542-C04, and No. FIS2009-12964- C05-04, and Consolider Ingenio 2010 under Grant No. CSD2009-00013 Imagine. We thank J. Garcia-Barriocanal for helpful discussions. We are indebted to the staff of SpLine for their help during the experimental work at ESRF. NO Junta de Comunidades de Castilla-La Mancha NO CAM NO Spanish MICINN NO Consolider Ingenio 2010 DS Docta Complutense RD 10 jun 2026