Processing of high conductive Bi2O3/8YSZ composites as SOFC electrolyte
Journal
Journal of Ceramic Processing Research
Journal Volume
20
Journal Issue
4
Pages
347-356
Date Issued
2019
Author(s)
Abstract
Dual-phasic composites consisted of continuous Bi2O3 matrix and 8 mol% yttria stabilized zirconia particulates were prepared by solid-state-sintering or liquid-phase-sintering, and investigated over the temperature range between 250-650oC to reveal good electrical conductivity and matched thermal expansion to the components used for intermediate-temperature solid oxide fuel cell (SOFC). Interface reactions occurred during sintering either at 750oC or 900oC could enhance the diffusion of Zr, Y and Bi ions, to form effective diffusion zone for stabilizing δ-Bi2O3 matrix. The results showed a dual-structure of 66 mol% 8YSZ-34 m% Bi2O3 with up to 76% δ-phase content was stabilized by solid-state sintering, surpassing a bulk conductivity of 10?2 Scm?1 at 500oC. The coefficient of thermal expansion value exhibited by the composite between 25oC and 650oC was found to be 10-12.2 ppm*K?1, which was in good agreement with that of CeO2-based electrolyte. Thus, it was confirmed that the addition of ZrO2 could stabilize the Bi2O3, by improving its capability as a solid electrolyte for intermediate temperature SOFC. ? 2019, Hanyang University. All rights reserved.
SDGs
Type
journal article