Preparation and electrical properties of a monophasic ZrO2Y2O3Bi2O3 solid electrolyte

Abstract

A preparation method is described of monophasic yttria stabilized zirconia doped with Bi203. This material is prepared from a homogeneous power which, after pressing, is sintered in a Bi203 atmosphere. The resulting ceramic has a composition of 0.78Zr02-0.206 YO1.5-O.O14Bi01. 5. The grain boundaries are enriched with bismuth. A relative density of 95% of the theoretical one is attained at a considerably lower temperature than the bismuth free sample. The electrical conductivities of the monophasic Bi doped and the Bi-free electrolyte material do not differ significantly.

Atomistic modeling of La3+ doping segregation effect on nanocrystalline yttria-stabilized zirconia

“…Y 3+ however, has a constant density over the whole structure, which results in a higher Y 3+ /Zr 4+ ratio at the GB itself, with 0.33 averaged over the two GB regions at Zr 4+ valleys as compared to 0.225 in the bulk phase (a segregation factor of 1.47). This is consistent with previous simulations 20 , in which Lee et al obtained a segregation factor of 1.2 in a Σ5(310)/[001] structure with the same doping concentration, and an experimental value of 1.5 as an average value over different GBs 25 .…”

Effect of Bismuth Oxide on the Microstructure and Electrical Conductivity of Yttria Stabilized Zirconia

“…These results are consistent with the XRD analysis results, which all indicate that more yttria (10 mol%) is needed in the system to stabilize zirconia and obtain a uniform, fully stabilized cubic structure. This dense and void-free morphology suggest that adding low-melting Bi 2 O 3 can significantly improve material density and promote grain growth because of introducing the liquid phase sintering effect [9,12,18]. The rounded rather than straight grain boundaries seen in the microstructure can be explained as the results of border infiltration occurring during the liquid sintering process.…”

“…Winnubst et al . [18] studied the effects of varying amounts of Bi 2 O 3 on the ionic conductivity of YSZ, but in those studies it was found that the enhancing effect of Bi 2 O 3 on the ionic conductivity of YSZ was very limited. Verkerk et al .…”

Suppression of Rhombohedral‐Phase Appearance and Low‐Temperature Sintering of Scandia‐Doped Cubic‐Zirconia

“…A similar phenomenon was reported for Y 2 O 3doped ZrO 2 . 17,19 In Fig. 4, measured grain size after 1 h of sintering is plotted against sintering temperature.…”

“…The distribution of the second phases affects the overall electrical properties of YSZ. 17 There is a lack of data concerning the influence of the addition of Bi 2 O 3 on the properties and structure of Sc 2 O 3 -doped ZrO 2 . Achievement of sufficient conductivity for low-temperature SOFC operation and establishment of a decreased-temperature cofiring schedule for componentsi.e., air electrode, electrolyte, interconnection, and fuel electrodeare desired.…”