Pr、Sm、Gd共掺杂CeO_(2)基中温固体氧化物燃料电池电解质材料的制备与电化学性能研究

Preparation and Electrochemical Properties of Pr,Sm and Gd Co-doped CeO_(2)-based Medium Temperature Solid Oxide Fuel Cell Electrolyte Materials

采用甘氨酸-硝酸盐法(GNP)合成了Pr、Sm、Gd共掺杂的CeO_(2)基Pr_(x)Gd_(x)Sm_(0.2-2x)Ce_(0.8)O_(2)-δ(PGSC0、PGSC2、PGSC4、PGSC6、PGSC8、PGSC10,x=0、0.02、0.04、0.06、0.08、0.10)电解质材料,并对其电化学性能进行了表征。XRD测试结果表明,PGSC电解质在600℃煅烧10 h后均形成立方萤石结构。拉曼光谱测试结果表明,Sm、Pr、Gd共掺杂可以有效提高氧空位浓度。PGSC10电解质在800℃时电导率约为0.1 S·cm^(-1),与 Sm_(0.2)Ce_(0.8)O_(1.9)(SDC)(0.115 S·cm^(-1))电解质大致相同,而在700℃以下,PGSC10电解质的电导率约为SDC的1.5倍,其活化能为0.377 eV,也明显低于SDC(0.626 eV)。因此,PGSC10是一种很有前途的中温固体氧化物燃料电池电解质材料。

CeO_(2)-based Pr_(x)Gd_(x)Sm_(0.2-2x)Ce_(0.8) O_(2)-δelectrolyte materials(PGSC0,PGSC2,PGSC4,PGSC6,PGSC8,PGSC10,x=0,0.02,0.04,0.06,0.08,0.10)co-doped with Pr,Sm and Gd were synthesized by glycine-nitrate method(GNP),and their electrochemical properties were characterized.XRD results show that PGSC electrolyte forms cubic fluorite structure after calcination at 600℃for 10 h.Raman spectroscopy test results show that co-doping of Sm,Pr and Gd can effectively increase the oxygen vacancy concentration.At 800℃,the conductivity of PGSC10 electrolyte is about 0.1 S·cm^(-1),which is roughly the same as that of Sm_(0.2)Ce_(0.8)O_(1.9)(SDC)(0.115 S·cm^(-1))electrolyte,while below 700℃,the conductivity of PGSC10 electrolyte is about 1.5 times that of SDC,and its activation energy is 0.377 eV.It is also significantly lower than SDC(0.626 eV).Therefore,PGSC10 is a promising medium temperature solid oxide fuel cell electrolyte material.