中温固体氧化物燃料电池Pr_(1.2)Sr_(0.8)NiO_4阴极材料的制备、结构和性能(英文)

Preparation,Structure and Properties of Pr_(1.2)Sr_(0.8)NiO_4 Cathode Materials for Intermediate-Temperature Solid Oxide Fuel Cells

以相应的氧化物粉末和盐为原料,通过甘氨酸-硝酸盐法合成出了中温固体氧化物燃料电池(IT-SOFC)Pr1.2Sr0.8NiO4(PSNO)阴极原料粉体,并制备出了烧结体试样.采用X射线衍射(XRD)分析对所合成粉体的相组成进行了分析,分别采用热膨胀仪和四端子法对PSNO烧结体试样的热膨胀系数和电导率进行了测定,同时对该阴极材料与Sm0.2Ce0.8O1.9(SCO)电解质材料的电化学阻抗谱(EIS)进行了测试分析.以SCO作电解质,分别以NiO/SCO和PSNO作阳极和阴极材料,制备出固体氧化物燃料单电池,并对其性能进行测试.实验结果表明,通过甘氨酸-硝酸盐法,在1050℃以上煅烧前驱体,可以获得具有K2NiF4结构的PSNO粉体.所制备的PS-NO烧结体试样在200-800℃间的热膨胀系数约为12×10-6K-1,在450℃下的电导率约为155S·cm-1,在400-800℃,平均电导活化能为0.034eV.电化学阻抗谱分析结果表明,在700℃下PSNO阴极和SCO电解质间的比表面阻抗(ASR)为0.37Ω·cm2,而Ni-SCO/SCO/PSNO单电池的比表面阻抗为0.61Ω·cm2;所制备的SOFC单电池在800℃下的输出功率为288mW·cm-2,开路电压为0.75V.本研究的初步结果表明PSNO材料是一种综合性能较为优良的新型中温固体氧化物燃料电池阴极材料.

Pr1.2Sr0.8NiO4 （PSNO） cathode material for an intermediate-temperature solid oxide fuel cell （IT-SOFC） was synthesized by a glycine-nitrate process.The phase structure of the synthesized powders was characterized by X-ray diffraction （XRD） analysis.The thermal expansion coefficient （TEC） and the electrical conductivity of the sintered PSNO samples were measured.Electrochemical impedance spectroscopy （EIS） measurements of the PSNO materials were carried out using an electrochemical workstation.Single cells based on the Sm0.2Ce0.8O1.9 （SCO） electrolyte were also assembled and tested.The results show that PSNO materials with a K2NiF4-type structure can be obtained by calcining the precursors at temperatures higher than 1050 ℃.The sintered PSNO samples have an average TEC of about 12×10-6 K-1 within 200-800 ℃,an electrical conductivity of 155 S·cm-1 at 450 ℃ and an average conduction activation energy of 0.034 eV at 400-800 ℃.Electrochemical impedance spectroscopy （EIS） shows that the area specific resistance （ASR） of the PSNO cathode on the SCO electrolyte is 0.37 Ω·cm2 and the ASR of the single Ni-SCO/SCO/PSNO cell is 0.61 Ω·cm2 at 700 ℃.The single Ni-SCO/SCO/PSNO cell produces a power density of 288 mW·cm-2 and an open circuit voltage of 0.75 V at 800 ℃.Preliminary work showed that the PSNO materials may be a potential cathode material for use in IT-SOFC.