【摘要】 采用固相法合成中温固体氧化物燃料电池（IT-SOFC）阴极材料Pr_1-xSrCo_0.5Ni_0.5O_4+δ(P_1-xSCN,x=0.00,0.05,0.10,0.15,0.20),并对材料的物相、热膨胀系数（TEC）、电导率、电极的微观形貌以及电化学性质进行表征。XRD结果表明,该材料形成单一的K₂NiF₄结构,空间群为I4/mmm,并与电解质材料Ce_0.9Gd_0.1O_1.95（CGO）具有良好的高温化学相容性。碘量法分析表明随着Pr离子缺位浓度增加,P_1-xSCN中Co/Ni离子平均化合价随着x的增加而升高,至x=0.10后逐渐降低,而氧空位含量逐渐升高。引入Pr离子缺位使材料的电导率明显提高,其中P_0.90SCN在700℃空气中电导率值为309 S·cm^-1。TEC测试结果显示,随着Pr缺位的增加,热膨胀系数逐渐增大,最大值为1.51×10^-5K^-1。交流阻抗谱（EIS）测试结果表明,Pr缺位明显降低了电极的极化阻抗值,P_0.90SCN阴极在700℃空气中的极化阻抗值为0.21Ω·cm²。电解质支撑NiO-CGO/CGO/P_0.90SCN单电池在700℃最大输出功率密度为197.8 mW·cm^-2。更多还原

【Abstract】 Intermediate temperature solid oxide fuel cells（IT-SOFCs）cathode materials Pr_1-xSrCo_0.5Ni_0.5O_4+δ(P_1-xSCN,x=0.0,0.05,0.10,0.15,0.20)are synthesized by solid-state reaction method.The phase,thermal expansion coefficient（TEC）,conductivity,electrode morphology and electrochemical properties are characterized.XRD results show that the oxides crystallize in a single K₂NiF₄structure with a space group of I4/mmm.The cathode materials exhibited good high temperature chemical compatibility with electrolyte Ce_0.9Gd_0.1O_1.95（CGO）.Iodometry analysis shows that with the increase of Pr³⁺vacancy concentration,the average valence of Co/Ni ions in oxides increased stepwise with the increase of x and then decreased after x=0.10,while the content of oxygen vacancy increased gradually.Introducing Pr³⁺vacancy significantly improved the conductivity of the material.The highest conductivity of 309 S·cm^-1was found in P_0.90SCN at 700℃in air.The thermal expansion measurement results show that TEC increased with the increase of Pr³⁺deficiency,and the maximum value is 1.51×10^-5K^-1.Electrochemical impedance spectroscopy（EIS）measurements show that Pr vacancy significantly reduced the polarization resistance of the electrode,and the smallest polarization resistance of 0.21Ω·cm²was obtained on P_0.90SCN cathode at700℃in air.The maximum output power density of electrolyte supported single cell NiO-CGO/CGO/P_0.90SCN was197.8 mW·cm^-2at 700℃.更多还原