摘要
通过柠檬酸硝酸盐燃烧法制备中温固体氧化物燃料电池(IT-SOFCs)双钙钛矿阴极材料SmBaCoFeO5+δ(SBCFO)粉体,并系统研究了该材料在中温段的晶体结构特征、热膨胀性能、离子–电子传输特性、电化学催化活性以及电池功率特性。结果表明:SBCFO在室温下为P mmm正交结构,在300℃时材料转变为P 4/mmm四方结构。SBCFO的热膨胀系数在25~200℃和200~900℃范围内分别为15.7×10^–6 K^–1和19.6×10^–6 K^–1。SBCFO阴极在600~800℃温度范围内电导率超过100 S/cm。在700,750,800和850℃时,空气(50 mL/min)气氛中,SBCFO/La0.8Sr0.2Ga0.8Mg0.2O3(LSGM)/SBCFO对称电池极化电阻分为0.210,0.100,0.054和0.032Ω?cm2。SBFCO双钙钛矿阴极氧还原反应的限速步骤是表面吸附氧分子解离成氧原子的过程。以SBCFO为阴极组装电解质支撑型单电池Ni-Gd0.1Ce0.9O2–δ/La0.4Ce0.6O2/LSGM(300μm)/SBCFO,800℃时,其最大功率密度达到831 mW/cm^2。
Sm BaCoFeO5+δ(SBCFO)double perovskite material as a high-performance cathode material for intermediate-temperature solid oxide fuel cells(IT-SOFCs)was synthesized by a citrate-nitrite combustion process.The crystal structure,thermal expansion coefficients,ionic-electronic transport property,electrochemical performance and cell power density of the material were evaluated.The results show that SBCFO has an orthorhombic structure Pmmm at room temperature,but transforms into a tetragonal structure P 4/mmm at 300℃.The thermal expansion coefficients of SBCFO are 15.7×10^-6 K^-1 and 19.6×10^-6 K^-1 at 25-200℃and 200-900℃,respectively.The electrical conductivity of SBFCO is higher than 100 S/cm at 600-800℃.The synthesized SBCFO exhibits a fast oxygen surface exchange and bulk diffusion kinetics,thus having a low polarization resistance.The area specific resistances of the SBCFO/La0.8 Sr0.2 Ga0.8 Mg0.2 O3(LSGM)/SBCFO symmetrical cell are 0.210,0.100,0.054,and 0.032Ω?cm2 at 700,750,800,and 850℃in air(50 m L/min),respectively.The rate-determining step of the oxidation-reduction reaction is the dissociation of adsorbed molecular oxygen into atomic oxygen.The electrolyte supported single cell,assembled with Ni-Gd0.1 Ce0.9 O2-δas an anode,LSGM(300μm)as an electrolyte and the SBFCO as a cathode,delivers a maximum power density of 831 m W/cm^2 at 800℃.
作者
杜志鸿
李科云
赵海雷
DU Zhihong;LI Keyun;ZHAO Hailei(School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China;Beijing Municipal Key Lab for Advanced Energy Materials and Technologies,Beijing 100083,China)
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2020年第2期187-194,共8页
Journal of The Chinese Ceramic Society
基金
国家重点研发计划(2018YFB1502202)
国家自然科学基金(U1637202,21805006)
中国博士后科学基金资助项目(2016M600041,2018T110044)
中央高校基本科研业务费专项资金资助(FRF-TP-16-033A1).
关键词
固体氧化物燃料电池
阴极
双钙钛矿
电化学性能
电导弛豫
solid oxide fuel cells
cathode
double perovskite
electrochemical property
conductivity relaxation
作者简介
第一作者:杜志鸿(1986—),男,博士,讲师;通信作者:赵海雷(1966—),女,博士,教授。
