Infiltration of La0·6Sr0·4FeO3-δ nanoparticles into YSZ scaffold for solid oxide fuel cell and solid oxide electrolysis cell

La0·6Sr0·4FeO3-δ (LSF) nanoparticles were infiltrated into porous YSZ scaffold to fabricate composite LSF-YSZ oxygen electrode for both solid oxide fuel cell (SOFC) and solid oxide electrolysis cell (SOEC). X-ray diffraction (XRD) pattern and scanning electron microscopy (SEM) images have demonstrated that the formation of LSF perovskite phase and uniform distribution of nano-structural LSF particles onto inner surface of the YSZ scaffold, respectively. Polarization curves and electrochemical impedance spectra (EIS) were employed for the characterization of electrochemical properties of the cell for both power generation and high-temperature steam electrolysis. Furthermore, the long-term durability of the LSF-infiltrated cell was galvanostatically carried out under both SOFC and SOEC operations. For SOFC operation, the cell experienced a significant degradation in the initial 50 h and subsequently was sustained at a stable operation, with overall ohmic and polarization resistance variation from 0.20 to 0.25 Ω cm2 and from 0.55 to 0.60 Ω cm2, respectively. For SOEC operation, the cell showed high long-term durability operation, with almost unchangeable ohmic resistance and slightly varied polarization resistance from 0.41 to 0.43 Ω cm2.