Sr-Co containing perovskite oxides are prospective air electrode candidates for reversible solid oxide cells(RSOCs).However,their efficiencies are limited by Sr segregation and the high thermal expansion coefficient(T...Sr-Co containing perovskite oxides are prospective air electrode candidates for reversible solid oxide cells(RSOCs).However,their efficiencies are limited by Sr segregation and the high thermal expansion coefficient(TEC)of Cobased perovskites.Herein,La_(0.6)Ca_(0.4)Fe_(0.8)Ni_(0.2)O_(3-δ)(LCa FN)is tailored as an Sr-Co-free perovskite air electrode for highperformance RSOCs.Compared with La_(0.6)Sr_(0.4)Fe_(0.8)Ni_(0.2)O_(3-δ)(LSFN)and La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)(LSCo F),LCa FN has a high electrical conductivity (297 S cm^(-1)),TEC compatibility(11.2×10^(-6)K^(-1)) and improved chemical stability.Moreover,LCa FN has high oxygen reduction reaction(ORR)activity with a low polarization resistance(0.06Ωcm^(2)) at 800℃.A single-cell NiYSZ/YSZ/gadolinium-doped ceria(GDC)/LCa FN-GDC operated at 800℃ yields a maximum power density of 1.08 W cm^(-2) using H_(2) as fuel.In the solid oxide electrolysis cell(SOEC)mode,the cell can achieve a current density of approximately 1.2 A cm^(-2) at 1.3 V with 70% humidity at 800℃.The cell exhibits good reversibility and remains stable in continuous SOEC and solid oxide fuel cell(SOFC)modes.These findings indicate the potential application of LCa FN as an air electrode material for RSOCs.展开更多
基金supported by the National Key Research&Development Program of China(2020YFB1506304,2017YFE0129300 and 2016YFE0126900)the National Natural Science Foundation of China(52072135,51672095 and U1910209)the Major Science and Technology Innovation Project of Hubei Province(2018AAA057)。
文摘Sr-Co containing perovskite oxides are prospective air electrode candidates for reversible solid oxide cells(RSOCs).However,their efficiencies are limited by Sr segregation and the high thermal expansion coefficient(TEC)of Cobased perovskites.Herein,La_(0.6)Ca_(0.4)Fe_(0.8)Ni_(0.2)O_(3-δ)(LCa FN)is tailored as an Sr-Co-free perovskite air electrode for highperformance RSOCs.Compared with La_(0.6)Sr_(0.4)Fe_(0.8)Ni_(0.2)O_(3-δ)(LSFN)and La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)(LSCo F),LCa FN has a high electrical conductivity (297 S cm^(-1)),TEC compatibility(11.2×10^(-6)K^(-1)) and improved chemical stability.Moreover,LCa FN has high oxygen reduction reaction(ORR)activity with a low polarization resistance(0.06Ωcm^(2)) at 800℃.A single-cell NiYSZ/YSZ/gadolinium-doped ceria(GDC)/LCa FN-GDC operated at 800℃ yields a maximum power density of 1.08 W cm^(-2) using H_(2) as fuel.In the solid oxide electrolysis cell(SOEC)mode,the cell can achieve a current density of approximately 1.2 A cm^(-2) at 1.3 V with 70% humidity at 800℃.The cell exhibits good reversibility and remains stable in continuous SOEC and solid oxide fuel cell(SOFC)modes.These findings indicate the potential application of LCa FN as an air electrode material for RSOCs.
