摘要
作为中温固体氧化物燃料电池的阴极材料,Ruddlesden-Popper结构化合物LaSrCoO_(4±δ)具有钴含量低、理论热膨胀系数小等优势.本文通过溶胶-凝胶过程制备得到该化合物,并对材料结构的热稳定性、热膨胀系数、电导率、电催化活性等进行了系统的研究.结果表明,化合物的晶型稳定,在900℃以下,晶格常数随温度的升高呈线性增加.相对于ABO_3型钙钛矿化合物La_(0.5)Sr_(0.5)CoO_(3-δ),化合物的热膨胀系数更低,与陶瓷电解质的热膨胀性能更加匹配.材料的高温导电性能良好,但导电行为复杂,存在着多种热激活传输机制.电池中,LaSrCoO_(4±δ)阴极的界面阻抗小,在800℃下为0.12Ω·cm^2,表现出良好的氧还原催化性能.电池在运行过程中,氧化物阴极的电化学性能有明显的衰退,但经过阴极极化后可重新活化.在800℃下,以Ni-Ce_(0.8)Sm_(0.2)O_(1.9)作阳极,电解质支撑型单电池的输出功率可达560 m W/cm^2.
As the cath0de candidate material of intermediate temperature solid-oxide fuel cells,Ruddlesden-Popper compound LaSrCoO（4 ± δ） is competitive due to its relatively low cobalt content and theoretically low thermal expansion coefficient.In this study,sol-gel route of soft chemistry method was employed to prepare this cathode material,and its structure,thermal expansion coefficient,electrical conductivity and electro-catalytic activity are systematically studied.As experiment turned out,crystal structure of this compound is very stable under thermal impact and below 900 ℃ lattice parameters increase approximately linearly with heating.Compared with ABO3-type perovskite La（0.5）Sr（0.5）CoO（3-δ）,thermal expansion coefficient was greatly reduced,which makes it more compatible with ceramic electrolytes.Electrical conductivity of this material is favorable,but its conduction behavior is rather complex and more than one thermal-activated transport mechanism are involved.Area specific resistance of cell＇s LaSrCoO（4 ± δ） cathode as low as 0.12 Ω·cm^2 at 800 ℃ is reached,showing the excellent electro-catalytic activity.The electrochemical performance of LaSrCoO（4 ± δ） cathode fades gradually with operation but can be regenerated after cathodic polarization.For LaSrCoO（4 ± δ） cathode,the power density as high as ca.560 m W/cm^2 at 800 ℃ is achieved in the electrolyte-supported single cell with Ni-Ce（0.8）Sm（0.2）O（1.9） as a node.
作者
李付绍
夏书标
闫宇星
成飞翔
LI Fushao;XIA Shubiao;YAN Yuxing;CHENG Feixiang(Chemical Function Materials Research Center,Qujing Normal University,Qujing,Yunnan 655011,China)
出处
《昆明理工大学学报（自然科学版）》
CAS
北大核心
2018年第5期14-21,共8页
Journal of Kunming University of Science and Technology(Natural Science)
基金
国家自然科学基金项目(51746048)
云南省地方高校联合基金(2017FH001-051)
关键词
固体氧化物燃料电池
阴极材料
电化学性能
材料表征
solid oxide fuel cell
cathode materials
electrochemical performance
material characterization
作者简介
李付绍（1978-），男，博士，副教授．主要研究方向：固体氧化物燃料电池与固态锂／钠离子电池．E—mail：lifushao@126．com;通信作者：成飞翔（1981-），男，博士，教授．主要研究方向：功能配合物．E—mail：chengfx2010@163．com
