Investigation of the Physical Properties of the La4Ni3-xBxO10-δ System (B = Cu, Fe) for Solid Oxide Fuel Cell Cathodes^

摘要

The lanthanum nickelate, La2NiO_(4+δ), of the Ruddlesden-Popper family (La_(n+1)Ni_nO_(3n+1); n =1) has been the source of much attention as a possible candidate for cathode-use in intermediate-temperature solid oxide fuel cells (IT-SOFC). This is in large part due to the enhanced observed oxide-ion diffusion coefficients together with reasonable electrical conductivity in the temperature range of interest. Recently, we have extended our studies to include the higher-order RP phases (n = 2 and 3) and have reported on the improved relative long-term stability and superior electrical conductivity of the n =3 phase, La4Ni3O_(10-δ) as well as its enhanced power density on LSGM-9182 electrolyte when compared to La2NiO_(4+δ). In this study, we investigate the higher-order n =3 copper-doped nickelate members of the Ruddlesden-Popper series, La4Ni(3-x)BxO_(10-δ) (B = Cu, Fe), for cathode-use in solid oxide fuel cells. Details regarding synthesis, structural analysis, electrical conductivity and electrode performance on LSGM are reported.^