Highly active and durable triple conducting composite air electrode for low-temperature protonic ceramic fuel cells  

作　　者：Qi Huang Shanshan Jiang Yujia Wang Jingjing Jiang Yubo Chen Jiahuan Xu Hao Qiu Chao Su Daifen Chen 

机构地区：[1]School of Energy and Power,Jiangsu University of Science and Technology,Zhenjiang 212100,China [2]Institute of Analysis and Testing,Beijing Academy of Science and Technology(Beijing Center for Physical and Chemical Analysis),Beijing 100089,China [3]School of Material Science and Engineering,Nanyang Technological University,50 Nanyang Avenue,Singapore 639798,Singapore [4]School of Science,Jiangsu University of Science and Technology,Zhenjiang 212100,China

出　　处：《Nano Research》2023年第7期9280-9288,共9页纳米研究（英文版）

基　　金：This research was financially supported by the National Natural Science Foundation of China(No.22179054);the National Natural Science Foundation of China(No.22101150);Natural Science Foundation of Jiangsu Province,China(No.BK20190965);Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.18KJB470011).

摘　　要：Protonic ceramic fuel cells(PCFCs)are more suitable for operation at low temperatures due to their smaller activation energy(Ea).Unfortunately,the utilization of PCFC technology at reduced temperatures is limited by the lack of durable and high-activity air electrodes.A lot number of cobalt-based oxides have been developed as air electrodes for PCFCs,due to their high oxygen reduction reaction(ORR)activity.However,cobalt-based oxides usually have more significant thermal expansion coefficients(TECs)and poor thermomechanical compatibility with electrolytes.These characteristics can lead to cell delamination and degradation.Herein,we rationally design a novel cobalt-containing composite cathode material with the nominal composition of Sr_(4)Fe_(4)Co_(2)O_(13)+δ(SFC).SFC is composed of tetragonal perovskite phase(Sr_(8)Fe_(8)O_(23)+δ,I4/mmm,81 wt.%)and spinel phase(Co_(3)O_(4),Fd3m,19 wt.%).The SFC composite cathode displays an ultra-high oxygen ionic conductivity(0.053 S·cm^(-1)at 550℃),superior CO_(2)tolerance,and suitable TEC value(17.01×10^(-6)K^(-1)).SFC has both the O_(2)^(-)/e^(-)conduction function,and the triple conducting(H^(+)/O_(2)^(-)/e^(-))capability was achieved by introducing the protonic conduction phase(BaZr_(0.2)Ce_(0.7)Y_(0.1)O_(3-δ),BZCY)to form SFC+BZCY(70 wt.%:30 wt.%).The SFC+BZCY composite electrode exhibits superior ORR activity at a reduced temperature with extremely low area-specific resistance(ASR,0.677Ω·cm^(2)at 550℃),profound peak power density(PPD,535 mW·cm^(-2)and 1.065 V at 550℃),extraordinarily long-term durability(>500 h for symmetrical cell and 350 h for single cell).Moreover,the composite has an ultra-low TEC value(15.96×10^(-6)K^(-1)).This study proves that SFC+BZCY with triple conducting capacity is an excellent cathode for low-temperature PCFCs.

关 键 词：protonic ceramic fuel cells spinel oxide composition tuning triple-conducting 

分 类 号：TM911.4[电气工程—电力电子与电力传动]