MgO掺杂Ce_(0.9)Sm_(0.1)O_(2-δ)固体电解质的结构和电性能

Structure and Electrical Properties of MgO-Doped Ce_(0.9)Sm_(0.1)O_(2-δ) Based Solid Electrolytes

采用溶胶-凝胶法合成SiO2含量为5.0×10-4(w)的Ce0.9Sm0.1O2-δ(SDC)粉体(SDCSi),并将0-3.0%(x)MgO分别加入到SDCSi陶瓷粉体中,用X射线衍射(XRD)和场发射扫描电子显微镜(FE-SEM)对材料进行表征,用交流阻抗谱(AC)测试材料的电性能.结果表明:MgO掺杂能使SDCSi的烧结温度降低100-200℃,提高陶瓷材料的致密度;清除或降低陶瓷材料晶界处SiO2杂质的有害影响,显著提高晶粒/晶界电导率和总电率;MgO掺杂到SDCSi具有烧结助剂和晶界杂质清除剂的双重作用.

The precursor powder of Ce0.9Sm0.1O2-δ（SDC） containing 5.0×10^-4（w） SiO2 as an impurity（SDCSi） was prepared by the sol-gel method and 0-3.0%（molar fraction,x） MgO was added to the SDCSi powder.The characterizations focused on phase structure,sintering behavior,relative density,electrical conductivity of all the samples were investigated by X-ray diffraction（XRD）,field emission scanning electron microscopy（FE-SEM）,and AC impedance spectroscopy.We find that MgO can reduce the sintering temperature about 100-200 ℃ and increase the relative density of the ceramics.The grain boundary conduction increased markedly for the 1.0%（x） MgO-loaded SDCSi ceramics as MgO can mitigate the harmful effects of the SiO2 impurity.These investigations have indicated that MgO is shown to be an effective sintering aid and a new scavenger of the grain boundary synchronously.