模拟环境下NiO-YSZ半电池还原过程分析

研究了固体氧化物燃料半电池在800℃模拟环境下阳极支撑材料的还原过程,分析讨论了还原程度、微观组织以及电解质薄膜中残余应力等随还原时间的变化规律,得到了NiO-YSZ半电池还原程度随还原时间的完整变化曲线。能谱分析表明:氧元素质量分数随还原时间的增加而减少,最低值为13.24%;镍元素质量分数随还原时间的增加而不断增多,最高值为49.56%;X射线应力分析发现:在还原过程中,电解质薄膜中的残余应力随还原时间的增加而逐渐变小,当还原时间达到12 h后,薄膜中的残余压应力值为394.35 MPa,降低到还原前残余应力的48.54%;扫描电镜观察发现:还原结束后,阳极支撑材料的微观结构中孔隙率增大。

Experimental Research on Reduction Stage in the Process of Using NiO-YSZ Half-Cell

The reduction stage in the process of using NiO-YSZ of solid oxide fuel half-cell at 800 °C has been experimentally investigated. The analysis of the microstructure and the reduction degree of anode support materials have been addressed. As well as the residual stress variation of electrolyte film after different reduction times has been studied from which the full curve variation of the reduction degree with different reduction time has been obtained. It can be seen from energy spectrum that the mass fraction of oxygen decreases with the increase of reduction time and the minimum value is 13.24%, while the mass fraction of nickel increases with the increase of reduction time and the maximum value is 49.56%. It can be indicated from the X-ray stress analysis that the residual stress of the electrolyte film reduces gradually with the increase of reduction time. The value of the residual stress in the film reaches 394.35 MPa when the reduction time reaches 12 h, which accounts for 48.54% of the residual stress before reduction. It is revealed from the scanning micrographs that the porosity increases in the anode support materials after reduction.