LaNiO3 is synthesized by the citric acid method, and LaNiO2.5 is prepared by hydride reduction reaction for the LaNiO3. Then a LaNiO2.5-Ba(Zr0.1Ce0.7 Y0.2) O3-δ composite cathode is manufactured with Ba(Zr0.1Ce0.7Y0.2) O3-δ as the electrolyte. The microstructure of the cathode is observed by scanning electron microscopy (SEM) and the electrochemical properties are characterized by both AC impedance and DC polarization measurements. The cathode polarization resistances get to 5. 27～0. 22 Ω· cm2 in a temperature range of 600～800℃. The rate-limiting of oxygen reduction reaction is governed by dissociation of oxygen molecules and charge transfer of oxygen atoms. The cathode overpotential reaches relatively high as 75 mV with current density of 0.05 A·cm-2 and at 750 ℃.%采用柠檬酸盐法合成了LaNiO3粉体,对其进行氢化物还原反应,制得具有单一结构的高氧缺位物相LaNiO2.5.以Ba(Zr0.1 Ce0.7 Y0.2)O3-δ (BZCY)为电解质制备了LaNiO2.5-BZCY复合阴极,利用扫描电镜对其微观结构进行了表征,并通过交流阻抗测试及直流极化测试对其电化学性能进行了研究.结果表明,LaNiO2.5-BZCY复合阴极在600～800℃范围内的极化面电阻为5.27～0.22 Ω·cm2,其氧还原反应速率控制步骤为氧分子的解离以及氧原子的电荷转移.另外,该阴极的极化过电势较高,在750℃及电流密度为0.05 A·cm-2时的极化过电势为75 mV.
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