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磷灰石型硅酸镧是新型的氧离子导体。本研究采用柠檬酸-硝酸盐溶胶-凝胶法制备磷灰石型硅酸镧(La10Si5.8Mg0.2O26.8)纳米粉末，将其与NiO纳米粉末按4：6的质量比、并添加不同量的NH4HCO3造孔剂进行混合，通过在1400℃温度下烧结及在600℃氢气中还原制备Ni/La10Si5.8Mg0.2O26.8多孔复合阳极。采用XRD和SEM对样品进行了物相和表面微观形貌表征。采用阿基米德排水法和交流阻抗谱测定了样品的孔隙率和阳极片的室温电阻。实验结果表明，多孔复合阳极片不含微观裂纹，未还原陶瓷样品的平均热膨胀系数为10.7×10-6 K-1。随着NH4HCO3造孔剂加入量的增加， Ni、磷灰石型硅酸镧的晶粒尺寸及气孔尺寸减小，孔隙率增加，孔隙率为30%~45%；阳极电阻先降低后增加。综合考虑阳极片的物相、表面微观形貌、孔隙率和电阻，以加入30wt% NH4HCO3造孔剂所制得的阳极片最佳。

Apatite-type lanthanum silicates are a new type of oxide-ion conductors. In the present research, nanosized apatite-type lanthanum silicate (La10Si5.8Mg0.2O26.8) powder was prepared through Sol-Gel method by using citric acid and nitrates. The nanosized lanthanum silicate powder was mixed with nanosized NiO powder according to weight ratio of 4:6, and with different amounts of NH4HCO3as pore-forming agent. Porous composite anodes of Ni/La10Si5.8Mg0.2O26.8 were fabricated through sintering at 1400℃ and then reduced in H2 atmosphere at 600℃. Phases, surface morphology and porosity of the samples were characterized by XRD, FE-SEM and Archimedes method, respectively. Resistance of the anodes at room temperature was determined by ac impedance spectroscopy. The results show that the prepared Ni/ La10Si5.8Mg0.2O26.8 porous composite anodes are micro-crack free and the mean thermal expansion coefficient before reduction is 10.7×10-6 K-1. With increasing amount of pore-forming agent NH4HCO3, sizes of Ni grains, apatite-type silicate grains and pores decrease, but the porosity increases within the range of 30%-45%. The resistance of the an-odes decreases at first and then increases as the amount of NH4HCO3 increases. Considering all these characteristics, including phases, surface morphology, porosity and resistance, the anode made with the pore-forming agent NH4HCO3 at ratio of 30wt% is the best.