SOFC的Ni-YSZ阳极功能层中Ni的迁移机制研究  

Migration Mechanism of Ni in Ni-YSZ Anode Functional Layer of SOFC

作　　者：高月[1] 黄笑莹 王帅[1] 吴雨杰 刘洁慧 吕喆[1] GAO Yue;HUANG Xiaoying;WANG Shuai;WU Yujie;LIU Jiehui;LYU Zhe(School of Physics,Harbin Institute of Technology,Harbin 150001,Heilongjiang,China)

机构地区：[1]哈尔滨工业大学物理学院,黑龙江哈尔滨150001

出　　处：《陶瓷学报》2022年第5期839-845,共7页Journal of Ceramics

基　　金：国家重点研发计划(2018YFB1502202);国家自然科学基金(51872067)。

摘　　要：Ni-YSZ阳极支撑固体氧化物燃料电池(SOFC)在长期运行过程中,存在因阳极功能层(AFL)中Ni有流失现象导致的阳极和电池性能衰退的问题,但Ni流失的微观过程和迁移驱动力尚缺乏明确的解释。首先,测试了干氢和湿氢作为燃料的SOFC的性能变化规律;然后,采用扫描电子显微镜—能量色散谱(SEM-EDS)和X-射线衍射(XRD)表征了阳极的AFL区及支撑体内不同层的Ni元素分布规律,发现使用湿氢燃料的电池性能衰退较慢且Ni迁移效应较弱。基于此现象,提出水分子、氢气分子与Ni(OH)_(2)分子碰撞导致的迁移模型,认为燃料氢气与产物水蒸气的定向迁移带给Ni(OH)_(2)不同的动量变化,这是Ni从AFL迁移到多孔Ni-YSZ支撑体中的驱动力,此机制成功解释了干、湿氢条件下性能衰退差异现象的原因。During the long-term operation of Ni-YSZ anode-supported membrane solid oxide fuel cells(SOFCs),degradation in cell performance occurs due to the loss of Ni in the anode functional layer(AFL).However,there is still no reasonable explanation for the microscopic process and migration driving force of the Ni loss phenomenon.The variation in performance SOFC with dry and wet hydrogen as fuel was first tested.Then,scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS)and X-ray diffraction(XRD)were used to characterize the distribution of Ni in the AFL region of the anode and different layers of the anode supporter.It was found that the performance of the cell using wet hydrogen fuel was less degraded and the Ni migration effect was depressed.Based on this observation,a Ni migration model was proposed,basing on the collisions of water molecules,hydrogen molecules and Ni(OH)_(2) molecules.It is assumed that the directional migrations of fuel hydrogen and product water vapor caused the difference in momentum-change of Ni(OH)_(2),thus proving that the driving force of Ni migration is from AFL to porous Ni-YSZ support.

关 键 词：SOFC 阳极 Ni迁移 性能衰退 分子碰撞 

分 类 号：TQ174.75[化学工程—陶瓷工业]