| 摘 要： | A composite interlayer comprised of gadolinia doped ceria(GDC) and Co/Fe oxide was prepared and investigated for solid oxide electrolysis cell with yttrium stabilized zirconia(YSZ) electrolyte and La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)(LSCF) anode. The interlayer was constructed of a base layer of GDC and a top layer of discrete Co_3O_4/FeCo_2O_4 particles. The presence of the GDC layer drastically alleviated the undesired reactions between LSCF and YSZ, and the presence of Co/Fe oxide led to further performance improvement. At 800 °C and 45% humidity, the cell with 70% Co/Fe-GDC interlayer achieved 0.98 A/cm~2 at 1.18 V, 14% higher than the cell without Co/Fe oxide. Electrochemical impedance spectroscopy(EIS) revealed that with higher Co/Fe content, both the ohmic resistance and the polarization resistance of the cell were reduced. It is suggested that Co/Fe oxide can react with the Sr species segregated from LSCF and Sr_(1-x)(Co,Fe)O_(3-δ), a compound with high catalytic activity and electronic conductivity. The Sr-capturing ability of Co/Fe oxide in combination with the Sr-blocking ability of GDC layer can effectively suppress the undesired reaction between LSCF and YSZ, and consequently improve the cell performance.
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