Enhanced ionic conductivity in heavily doped ceria nanoceramics

M.G. BELLINO; D.G. LAMAS; N.E. WALSÖE DE RECA

Leipzig, Alemania

Congreso; Diffusion Fundamentals I: Basic Principles of Theory, Experiment and Application; 2005

In this work, we present the electrical properties of nanostructured, heavily yttria- or samaria-doped ceria ceramics. We demonstrate that these nanostructured samples exhibit a remarkable enhancement in the total ionic conductivity, of about one order of magnitude, compared with the intrinsic bulk conductivity of conventional microcrystalline ceramics. This effect is attributed to the predominance of grain-boundary conduction in the nanostructured materials, coupled with an increase in the grain-boundary ionic diffusivity with decreasing grain size.