复合固体电解质NGM-GYDC的微观结构和电性能

Microstructure and Electrical Properties of Composite Electrolytes of NGM-GYDC

用溶胶-凝胶法在煅烧温度800℃和1 200℃制备Ce_(0.8)Gd_(0.15)Y_(0.05)O_(2-δ)(GYDC)和NdGa_(0.9)Mg_(0.1)O_(3-δ)(NGM)电解质初始粉末,以GYDC为基底材料,将GYDC和NGM按物质的量比1∶0.05,1∶0.10,1∶0.15进行机械混合,烧结温度为1 300℃,1 400℃和1 500℃制备NGM-GYDC复合电解质材料.利用X射线衍射(XRD),扫描电子显微镜(SEM)和交流阻抗谱研究NGM的掺入量及烧结温度对NGM-GYDC复合电解质材料的微观结构和电性能的影响.研究结果表明:1 300℃烧结10 h,所有复合电解质材料均为立方萤石结构,晶粒近似球形,分布均匀,在所有复合电解质材料中,010NGM-GYDC具有较高的电导率和较低的活化能,在600℃时电导率σ600℃=2.81×10^(-3)S/cm,活化能Ea=0.83 eV,比基底材料GYDC的电导率(σ600℃=1.31×10^(-3)S/cm,Ea=0.92 eV)提高2.15倍.

Initial electrolyte powders of Ce0.8Gd0.15Y0.05O2-δ（ GYDC） and NdGa0.9Mg0.1O3-δ（ NGM） were prepared by sol-gel methods and thermally treated at 800 ℃ and 1 200 ℃,respectively. GYDC was mechanically mixed with NGM by ratios of 1 ∶ 0. 05,1 ∶ 0. 10,and 1 ∶ 0. 15 and calcined at 1 300 ℃,1 400 ℃,and 1 500 ℃to obtain the composite electrolyte material of NGM-GYDC. The characterization techniques,including X-ray diffraction（ XRD）,scanning electron microscope（ SEM）,and electrochemical impedance spectroscopy analyses,were used to study the effect of the NGM content and calcinations temperature on the microstructure and electrical properties of the composite electrolyte material of NGM-GYDC. Single phase cubic fluorite structure was found for all NGM-GYDC materials calcined at 1 300 ℃ for 10 h. The crystallites of all samples at 1 300 ℃ were spherelike and well-distributed. Among composite electrolyte materials,the sample of 010NGM-GYDC exhibited features of relatively high conductivity and low activation energy. At 600 ℃,its conductivity was σ600 ℃= 2. 81 ×10^-3S/cm and the activation energy was Ea= 0. 83 eV. The conductivity was higher by 2. 15 times than that of the base material of NGM,which was σ600 ℃= 1. 31 ×10^-3S/cm and Ea= 0. 92 eV.