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The temperature (700 8 00 ° C) solid oxide fuel cell (IT-SOFC) performance and stability, thermal stress is small, long battery life, and can use inexpensive, high conductivity, easy processing of bis plate metal alloys. Cr alloy and stainless steel is most widely application prospect. However, Cr alloys are used for bipolar plates of the SOFC, the traditional (La, Sr) MnO3 (LSM) and (La, Sr) (Co, Fe) O3 (LSCF) cathode material such as chromium poisoning due to the rapid decline in performance . So looking for a new high-performance and has anti chromium poisoning of the cathode material is imminent. LaNi 0.6 Fe 0.4 O 3-δ (LNF) material with good performance and high resistance to chromium poisoning electrochemical catalytic performance. This paper studies the LaNi 0.6 Fe 0.4 O 3-δ cathode material preparation, characterization and performance improvements. Prepared by low temperature combustion LaNi 0.6 Fe 0.4 O 3-δ materials. X-ray diffraction (XRD) shows 600 ° C can be obtained after calcining the precursor single perovskite phase, transmission electron microscopy (TEM) shows a particle size of 50-100nm. LaNi 0.6 Fe 0.4 O 3-δ and Sc 0.1 Zr 0.9 O < sub> 1.95 (ScSZ) at 1100 ° C the reaction of a large number of insulating phase La2Zr2O7. Screen printing preparation LNF / ScSZ / LNF symmetrical batteries. AC impedance spectra show 1050 ° C calcined battery cathode polarization resistance min at 850 ° C, 800 ° C, 750 ° C, 700 ° C and 650 ° C, respectively, the polarization resistance 0.12Ω · cm 2 < / sup>, 0.28Ω · cm 2 , 0.70Ω · cm 2 , 1.91Ω · cm 2 and 5.62Ω · cm 2 . Fe-Cr alloy is present, the cathode ohmic resistance and polarization resistance are increased with time. Cathode / electrolyte interface depositing small low conductivity Cr2O3 (s), active particles slow diffusion of the three-phase interface, increasing cathodic polarization resistance. First synthesized by impregnation method LaNi 0.6 Fe 0.4 O 3-δ -Gd 0.2 Ce 0.8 < / sub> O 2-α new composite cathodes. Gd 0.2 Ce 0.8 O 2-α (GDC) impregnation amount x = 21% of the LNF-GDC composite cathodes (LNF-GDC21) Performance optimum, the 850 ° C, 800 ° C, 750 ° C, 700 ° C and 650 ° C, respectively, the polarization resistance of 0.03Ω · cm 2 , 0.06Ω · cm 2 , 0.12Ω · cm 2 , 0.29Ω · cm 2 and 0.71Ω · cm 2 . 750 ° C composite cathode polarization resistance (0.12Ω · cm 2 ) about more than pure LNF (0.70Ω · cm 2 ) decreased by 7-fold. LNF-GDC21 composite cathode cathode activation energy is the smallest of all, as 136.80kJ/mol. The presence of Fe-Cr alloys, ohmic resistance and polarization resistance at 0 6 10h with time of slow growth, 634 1 042h its polarization resistance stabilized at 2.94Ω · cm 2 , ohmic resistance stabilized at 0.92Ω · cm 2 . Cathode / electrolyte interface chromium deposition so few LNF-GDC21 new composite cathode in Fe-Cr alloy precursor 1042h also maintain a low polarization resistance and stability. LNF-GDC21 new composite cathode has a high resistance to chromium poisoning performance and stability.
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