Effect of the grain size on the conductivity of high-purity pore-free ceramics Y2O8–ZrO2

Abstract

Measurements of the electrolyte overall resistance as well as the grain volume and boundary resistances comprising it, reveal that the grain volume resistance remains constant while that of grain boundaries and accordingly of the electrolyte decreases with the increase of the average grain size and sintering temperature. The activation energy for conductivity of the grain boundaries is higher than that of the grain volume due to which at high temperatures the electrolyte conductivity is mainly determined by the grain conductivity, while at low temperatures it is the boundary conductivity that matters.

Novel Zirconia-Based Superionic Conductors: The Electrical Conductivity of Y–Zr–O–N Materials

“…In addition, a change in the slope of the Arrhenius plot is observed, which becomes less marked with decreasing yttria content. These effects have been widely discussed in the literature [e.g., [25][26][27][28][29]. The common explanation is that two regions of ionic conductivity exist.…”

Kinetic demixing and grain boundary conductivity of yttria-doped zirconia part I - experimental observations

“…1 The grain boundary conductivity varies from sample to sample, as illustrated in Figs. 2-6, but all plots show increase in grain size [5,8,17,23,24]. Furthermore, the grain boundary conductivity of samples A, less contaminated with silicon, is higher than that of samples B (Figs.…”

A brief review of the ionic conductivity enhancement for selected oxide electrolytes

“…Ioffe et al have prepared 5.7 mol% YSZ specimens by hotpressing at 1200 • C and investigated the effect of grain size between ∼0.2 and ∼18 m on the conductivity of YSZ polycrystalline materials [93]. Dijk and Burggraaf investigated the effect of grain size between 0.4 and 20 m on the ionic conductivity of Gd x Zr (1−x) O (2−0.5x) [58].…”