Influences of Bi0.75Y0.25O1.5 addition on the microstructure and ionic conductivity of Ce0.8Y0.2O1.9 ceramics |
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| Authors: | Wenke Liang Bin Meng Qingfei Xiao Xinyu Ping Qian Zheng Chen Li Zhidong Xia |
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| Affiliation: | 1. Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, PR China;2. School of Land Resource Engineering, Kunming University of Science and Technology, Kunming, PR China |
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| Abstract: | A second phase of Y2O3-stabilized Bi2O3 (Bi0.75Y0.25O1.5,YSB) is introduced into Y2O3-doped CeO2 (Ce0.8Y0.2O1.9,YDC) as a sintering additive and the composite ceramics of YDC-xYSB (x = 0, 5, 10, 20, 30, 40 wt%) are prepared through sintering at 1100°C for 6 h in air atmosphere. The YDC-xYSB ceramics are composed of both YDC and YSB with cubic fluorite structure, and no other impurity phases are detected in XRD patterns. The relative density of YDC-xYSB rises firstly for x ≤5 wt%, and then it declines with YSB addition from 5 to 40 wt%. The average grain size of YDC decreases from 270 nm to 85.7 nm with YSB addition from 0 to 40 wt%. The YSB phase segregates at the grain boundaries of YDC based on the TEM analysis result. The ionic conductivity of YDC-xYSB (x ≥5 wt%) is lower than that of YDC in the test temperature of 200°C–500°C, while it gradually exceeds that of YDC in 500°C–750°C. At 750°C, the conductivity of YDC-30%YSB (6.22 × 10?2 S/cm) is 1.35 times higher than that of YDC (4.6 × 10?2 S/cm). The YSB addition can improve the ionic conductivity of YDC in 500°C–750°C and decrease its sintering temperature. |
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| Keywords: | bismuth oxide composite ceramics ionic conductivity sintering aid Y2O3-doped CeO2 |
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