利用溶胶 凝胶法低温合成了BaCe0 .8Ln0 .2 O2 .9(Ln =Gd ,Sm ,Eu)固体电解质 ,X射线粉末衍射表明 90 0℃即形成正交钙钛矿结构 ,较高温固相反应合成温度降低了约 6 0 0℃ .测定了样品的阻抗谱和电导率 ,研究了其导电机理 ,溶胶 凝胶法合成可减小或消除固体电解质的晶界电阻 ,80 0℃时BaCe0 .8Gd0 .2 O2 .9的σ =7.87× 10 -2S·cm-1,以它为电解质的氢氧燃料电池开路电压接近 1V ,最大输出功率密度为 30mW·cm-2 . The solid electrolyte of BaCe0.8Ln0.2O2.9 (Ln = Gd, Sm, Eu) was synthesized at low temperature by sol-gel method. The X-ray powder diffraction showed that the orthorhombic perovskite structure was formed at 90 0 ℃. The higher temperature solid state reaction The synthesis temperature was reduced by about 600 ℃. The impedance spectra and conductivity of the samples were measured. The conduction mechanism was studied. The sol-gel synthesis can reduce or eliminate the grain boundary resistance of the solid electrolyte. When BaCe0.8Gd0 Σ2 of O2 .9 = 7.87 × 10 -2S · cm-1, the open circuit voltage of the oxy-fuel cell with it as electrolyte is close to 1V and the maximum output power density is 30mW · cm-2.