Pyrochlore La_(2)Zr_(2-x)Ni_(x)O_(7)anodes for direct ammonia solid oxide fuel cells  

作　　者：Shiqing Yang Yijie Gao Xinmin Wang Fulan Zhong Huihuang Fang Yu Luo Lilong Jiang 

机构地区：[1]National Engineering Research Center of Chemical Fertilizer Catalyst(NERC-CFC),College of Chemical Engineering,Fuzhou University,Fuzhou 350002,China

出　　处：《Frontiers in Energy》2024年第5期699-711,共13页能源前沿（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.22378069,22278081,and 22308055);the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(Grant No.22221005);the National Key R&D Program of China(Grant Nos.2022YFB4003701 and 2022YFB4002404);the Natural Science Foundation of Fujian Province,China(Grant Nos.2023J01066 and 2022J05027);the Talent Program of Fuzhou University(Grant No.XRC-22036).

摘　　要：Developing efficient anode catalysts for direct ammonia solid oxide fuel cells(NH_(3)-SOFCs)under intermediate-temperatures is of great importance,in support of hydrogen economy via ammonia utilization.In the present work,the pyrochlore-type La_(2)Zr_(2-x)Ni_(x)O_(7+δ)(LZN_(x),x=0,0.02,0.05,0.08,0.10)oxides were synthesized as potential anode catalysts of NH_(3)-SOFCs due to the abundant Frankel defect that contributes to the good conductivity and oxygen ion mobility capacity.The effects of different content of Ni^(2+)doping on the crystal structure,surface morphology,thermal matching with YSZ(Yttria-stabilized zirconia),conductivity,and electrochemical performance of pyrochlore oxides were examined using different characterization techniques.The findings indicate that the LZN_(x)oxide behaves as an n-type semiconductor and exhibits an excellent high-temperature chemical compatibility and thermal matching with the YSZ electrolyte.Furthermore,LZN_(0.05)exhibits the smallest conductive band potential and bandgap,making it have a higher power density as anode material for NH_(3)-SOFCs compared to other anodes.As a result,the maximum power density of the LZN_(0.05)-40YSZ composite anode reaches 100.86 mW/cm^(2)at 800℃,which is 1.8 times greater than that of NiO-based NH_(3)-SOFCs(56.75 mW/cm^(2))under identical flow rate and temperature conditions.The extended durability indicates that the NH_(3)-SOFCs utilizing the LZN_(0.05)-40YSZ composite anode exhibits a negligible voltage degradation following uninterrupted operation at 800℃for 100 h.

关 键 词：anode catalyst ammonia oxidation Ni particles NH_(3)-SOFCs 

分 类 号：TM911.4[电气工程—电力电子与电力传动]