Electrical conductivity properties of porous SmBaCo2O5+d and SmBa0.5Sr0.5Co2O5+d layered perovskite oxide systems for solid oxide fuel cell

Generation of nanoflowers and nanoneedles on Co-based layered perovskite of IT-SOFC cathode affecting electrical conductivities

“…Firstly the electrical conductivity of the porous cathodes used in this research with a thickness of 20-30 micrometers cannot be measured without the use of an electrolyte support and secondly the porous cathode in the form of a thin film requires mechanical support from the electrolyte substrates. Therefore, the following process is required [24,25]. First, 9 g of Ce0.9Gd0.1O2-d (CGO91) powder was compressed into a rectangular metal mold (30 x 23 x 2 mm) with 1.5 x 10 3 kg/m 2 pressure to form the electrolyte substrate.…”

“…The zirconia beads were removed from the slurry and the remaining part was stirred at room temperature to form a cathode ink paste. The specific process can be found in a previously published study by our research group [23][24][25][26][27][28]. The cathode ink was thinly screenprinted on the sintered CGO91 electrolyte substrate using a mesh (23 x 6 mm).…”

“…In addition, the current value at which the porous cathode was destroyed differed in the air atmosphere and nitrogen atmosphere. For example, when assuming that currents corresponding to a high current are applied in a nitrogen atmosphere, an overvoltage may occur in a P-type cathode with low conductivity due to a low oxygen partial pressure, and the porous cathode may be destroyed [24]. Thus, in this condition, the applied current value differed according to the atmosphere condition.…”

“…Thus, in this condition, the applied current value differed according to the atmosphere condition. Therefore, the electrical conductivity measurement conditions for the porous cathode were referenced from a previous study reported by our research group [24].…”

“…In addition, a SBSCO cathode with these characteristics was fabricated with two microstructures (dense and porous cathode) and the relationship between the electrochemical properties and microstructure was analyzed. It has been reported that there is a difference in the movement of charge carriers between a porous and a dense cathode due to a difference in the microstructure, which results in differences in electrical conductivity [24].…”