YANG Lin, LUO Linghong, WU Yefan, SHI Jijun, CHENG Liang, HU Weiqi
(Jingdezhen Ceramic Institute, Jingdezhen 333001, Jiangxi, China)
Abstract：GDC (10mol%Gd2O3 doped CeO2) nano-powder was prepared using urea and NH4HCO3 as precipitants via the method of precipitation. The nanopowder prepared using NH4HCO3 as precipitator had spherical morphology. It could effectively promote sintering densification (the theoretical density sintered at 1380 ℃ could reach 96%) and was appropriate to be used as the material for tape casting the (NiO+YSZ||YSZ||GDC||LSCF) interlayer for single cell of SOFC. The sintering performance and electrical properties of the two kinds of GDC nano-powders were studied. The maximum power density of the single cell was 0.66 W/cm2 when 3%H2O+H2 was used as the fuel and the air as the oxidizing gas at 700 ℃. The GDC nanopowder prepared using urea as the precipitator, large in particle size and low in productivity, had rodlike structure. The morphology, utterly different from the spherical of the YSZ and unfavorable for densely packing, could result in a loose bond between two layers. So the maximum power density of the single cell prepared and tested in the same way was only 0.42 W/cm2.
Key words: solid oxide fuel cell (SOFC); interlayer; GDC; aqueous tape casting method