Microtubular SOFC using doped LaGaO₃ electrolyte film prepared with dip coating method

Abstract

Preparation of Microtubular cell using doped lanthanum gallate (LSGM) electrolyte with a dip coating and co-sintering process was studied. In order to suppress Ni diffusion from Ni-based anode substrate to LSGM electrolyte layer, Ti added La-doped ceria (Ti-LDC) was inserted as buffer layer. The amount of Ni diffused in LSGM electrolyte was investigated by EDX analysis as a function of sintering temperatures. It was found that sintering at 1350°C is suitable from the sintering density and the Ni diffusion. The cell sintered at 1350°C exhibited the higher power density than that of the conventional LSGM micro-tubular cell, even though a small amount of Ni diffusion was still observed at the Ti-LDC buffer layer/LSGM electrolyte interface. The micro-tubular cell with around 50 µm thickness showed the open circuit potential higher than 1.0 V and the maximum power density of 0.69, 0.31 and 0.12 W/cm² at 700, 600 and 500°C, respectively, were achieved.