质子导体固体氧化物燃料电池的PrBa_(0.5)Sr_(0.5)Cu_2O_(6-δ)复合阴极材料

PrBa_(0.5)Sr_(0.5)Cu_2O_(6-δ) as Composite Cathode for Proton-conducting Solid Oxide Fuel Cells

采用柠檬酸盐燃烧法制备了无钴双钙钛矿氧化物PrBa_(0.5)Sr_(0.5)Cu_2O_(6-δ)(PBSC)粉体,探究其作为质子导体固体氧化物燃料电池(H-SOFCs)阴极材料的可行性。研究了它与质子导体电解质BaZr_(0.1)Ce_(0.7)Y_(0.2)O_(3-δ)(BZCY)之间的化学相容性,分析了单相阴极PBSC、复合阴极PBSC-BZCY与电解质之间的热匹配性,并测试了单电池的电化学性能。结果发现,以PBSC为阴极、NiO-BZCY为阳极、BZCY为电解质的单电池在750℃时的最大功率密度为230 mW·cm^(-2),表明PBSC可作为H-SOFCs的阴极材料。而以PBSC-BZCY为阴极的单电池在750℃时的最大功率密度高达669 mW·cm^(-2)。复合阴极电池性能的大幅提高主要与阴极反应从单相阴极/电解质界面扩展到复合阴极电池的整个阴极区域,大幅降低电池电阻有关。PBSC-BZCY复合阴极在H-SOFCs中的应用具有较好的前景。

Cobalt-free double perovskite PrBa 0.5Sr0.5 Cu2O 6-δ(PBSC)powders were prepared using a citric acid-nitrate gel combustion process and stu-dies were performed to investigate the possibility of PBSC working as cathode for proton-conducting solid oxide fuel cells(H-SOFCs).The chemical compatibility with proton conductor BaZr 0.1Ce 0.7Y0.2O3-δ(BZCY)and thermal matching between the single-phase cathode PBSC,composite cathode PBSC-BZCY and the electrolyte were investigated.Electrochemical properties of H-SOFCs with PBSC or PBSC-BZCY cathodes were studied.Results show that for H-SOFCs constructed with PBSC as cathode,BZCY as electrolyte and NiO-BZCY as anode support,the peak power density is 230 mW·cm^-2 at 750℃,indicating that PBSC could be a candidate for cathode of H-SOFCs;while for single cell constructed with PBSC-BZCY as cathode,the peak power density is 669 mW·cm^-2 at 750℃.The significant improvement on the performance of single cells with composite cathode should be mainly attributed to the large decrease in resistance resulted from the extended reaction area as the whole cathode for composite cathode cells comparing with that of PBSC/electrolyte interface for single phase cathode cells.The results indicate the good prospects for PBSC-BZCY composite cathode in H-SOFCs application.