BaO修饰的Ni0.5Cu0.5Ox-YSZ阳极的制备及性能

Preparation and properties of BaO modified Ni0.5Cu0.5Ox-YSZ anode

阳极积碳会导致直接氧化甲烷型固体氧化物燃料电池(SOFCs)的性能衰减,为增加甲烷燃料中电池的稳定性,采用硬模板法与分次浸渍法制备BaO/Ni0.5Cu0.5Ox包覆柱状YSZ复合阳极材料,制作单电池BaO/Ni0.5Cu0.5Ox-YSZ/YSZ/LSM,并进行电性能与长期稳定性测试。用SEM(扫描电子显微镜)与EDS(能谱议)对实验后的阳极结构与表面成分进行观察与分析。结果表明:在800℃的甲烷环境下,单电池的最大功率密度为323 mW/cm2;运行100 h后,电压降只有2.12%。实验后的阳极SEM像表明,阳极呈立体多孔结构,有利于燃料气体与反应废气的扩散;催化金属颗粒均匀包覆着柱状YSZ,扩大了电化学反应区域。EDS能谱分析表明,有少量积碳形成,阳极孔道未被堵塞,证明了阳极结构的稳定。单电池稳定性的增强归功于立体多孔阳极的制备与碱性氧化物BaO的加入。

Carbon formation will cause performance degradation of direct oxidized methane solid oxide fuel cells(SOFCs).A composite anode material of BaO/Ni0.5Cu0.5Ox coated columnar-shaped YSZ was investigated to enhance the stability of SOFC.The composite materials were prepared by hard template method combined with wet impregnation method.The performance and long-term stability of the unit cell with BaO/Ni0.5Cu0.5Ox-YSZ anode were tested.The structure and surface composition of the anode were observed and analyzed by scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS),respectively.The results indicate that a maximum power density of 323 mW/cm^2 is obtained at 800℃,the cell shows no degradation and there is a voltage drop of 2.12%after operation for 100 h.The SEM observation shows a stereoscopic anode with high porosity which is beneficial for gas diffusion.The columnar-shaped YSZ anode scaffolds are evenly coated by catalytic metal particles,leading to extended active reaction sites.The EDS analysis demonstrates that less carbon forms than that of anode without BaO and channels of anode are not blocked,indicating that the prepared anode has higher coking resistance.The improved stability of the cell is attributed to the 3D porous anode combined with the addition of BaO in anode.