低溫燒結多元摻雜CeO_2基固態電解質之研究

A study on lowering the sintering temperature for multi-element-Doped, CeO_2-Based Electrolytes

王耀明(Y.M. Wang) ； 謝濠全(H.C. Shie) ； 張宏宜(H.Y. Chang)

《鑛冶：中國鑛冶工程學會會刊》 53卷3期 (2009/09) Pp. 17-23

https://doi.org/10.30069/MM.200909_53(3).0002

摘要

氧化鈰摻雜二價、三價金屬，做為中溫的固態氧化物燃料電池電解質擁有高的氧離子導電率。然而多元素的摻雜氧化鈰（La_(1-x-y)Sr_xBa_y）_(0.175)Ce_(0.825)O_(2-δ)（LSBC）很難在低的煆燒溫度下得到純相結構，透過傳統固態法（SS）製備組成， 在傳統的燒結狀況下，燒結溫度也必需大於1500℃才可得到純相結構以及緻密的燒結密度。利用溶液蒸發法（SV）合成出50nm的LSBC粒子，低於700℃的煆燒溫度就可以得到純相的螢石結構，SV所得粉末可以降低燒結溫度至1300℃，遠低於SS方法的1500℃°微波燒結SV試片，燒結條件1400℃／15min，檢測溫度600℃的氧離子導電率有0.01S／cm，並且密度可以達到98％且晶粒大小約在1μm左右。

關鍵字

多元摻雜氧化鈰 ； 固態氧化物燃料電池 ； 溶液蒸發法 ； 微波燒結

並列摘要

CeO_2 materials doped with the di-or tri-valent metals possess high oxygen ionic conductivity for potential electrolyte use in intermediate temperature solid oxide fuel cell (IT-SOFC). However, multi-elements doped CeO_2-based electrolyte, (La_(1-x-y)Sr_xBa_y)_(0.175)Ce_(0.825)O_(2-δ) (LSBC) in this work, with pure phase is difficultly synthesized at low calcination temperature. High sintering temperature, e.g.,＞1500℃, is also needed in conventional mixed oxide method to obtain pure fluorite structure and high density. In this work, nanoparticles less than 50nm of LSBC can be prepared by solution-evaporation method (SV) at constant temperature. Pure fluorite crystal structure can be obtained as low as 700℃. The sintering densification temperature of 1300℃ for LSBC prepared by solution-evaporation method is far lower than the 1500℃ by mixed oxide method. The ionic conductivity of 1400℃-microwave sintered LSBC prepared by solution-evaporation method is about 0.01 S/cm at 600℃. The relative density of microwave sintering reaches up to 98%. Small grain size of about 1μm average is observed for 1400℃-microwave sintered LSBC by solution-evaporation method preparation.

並列關鍵字

multi-elements doped CeO_2 ； SOFC ； solution evaporation ； microwave sintering