Co元素掺杂对CeO_2基固态电解质导电行为的影响

Effects of Co-dopings on Electrical Behaviors of CeO_2-based Solid Electrolyte

分别采用晶格固溶(Solid Solution,SS)和晶界择优偏聚(Grain Boundary Segregation,GBS)两种方式将Co元素添加至Gd掺杂的CeO_2粉末(GDC)内,研究两种添加方式对GDC电导行为的影响。首先采用共沉淀法制备10%Gd(摩尔分数,下同)掺杂的GDC粉末(10GDC),再分别通过以上两种方式将1%Co元素添加至10GDC粉末中,得到10GDC-1Co(SS)和10GDC-1Co(GBS)粉末样品。上述粉末样品中只含有CeO_2固溶体相,晶粒尺寸范围为10.1~12nm。将Co掺杂前后粉末样品在1000℃下烧结1h,分别得到10GDC,10GDC-1Co(SS)和10GDC-1Co(GBS)片状陶瓷样品。烧结后所有陶瓷样品中均只含有CeO_2固溶体相,晶粒尺寸范围为44.5~59.7nm。10GDC-1Co(SS)和10GDC-1Co(GBS)样品的电导率均高于10GDC样品的电导率,当测试温度低于430℃时,10GDC-1Co(GBS)样品的电导率高于10GDC-1Co(SS)样品;当测试温度高于430℃时,10GDC-1Co(SS)样品的电导率高于10GDC-1Co(GBS)样品。

Co element was added into Gd doped ceria （GDC） powders by two methods namely lattice solution and preferred grain boundary segregation, respectively. The 10% （mole fraction, the same below） Gd doped ceria （10GDC） solid solution powders were co precipitated and then doped with 1 Co by the means of the two ways. These powders were named as 10GDC 1Co （SS） and 10GDC 1Co （GBS）, respectively. Then the powders above were sintered at 1000℃ for lh to obtain 10GDC, 10GDC 1Co （SS） and 10GDC 1Co （GBS） ceramic samples. All the synthesized powders and sintered samples only consist of the CeO2 solid solution phase, and their grain sizes are 10.1 12nm and 59.8-112nm, respectively. The conductivities of 10GDC 1Co （SS） and 10GDC 1Co （GBS） samples are higher than that of 10GDC samples. When the test temperature is lower than 430℃, the conductivi