采用柠檬酸-硝酸盐自蔓延燃烧法分别合成了Pr_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)(PSCF)和Gd_(0.2)Ce_(0.8)O_(2-δ)(GDC)粉体,高温固相法合成La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_(3-δ)(LSGM)电解质粉体。以LSGM为电解质,PSCF同时...采用柠檬酸-硝酸盐自蔓延燃烧法分别合成了Pr_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)(PSCF)和Gd_(0.2)Ce_(0.8)O_(2-δ)(GDC)粉体,高温固相法合成La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_(3-δ)(LSGM)电解质粉体。以LSGM为电解质,PSCF同时作为阴极和阳极,GDC作为功能层材料,构建了对称固体氧化物燃料电池PSCF│GDC│LSGM│GDC│PSCF。利用X射线衍射法研究材料的成相以及相互间的化学稳定性,交流阻抗法记录界面极化行为,用扫描电子显微镜观察电池的断面微结构,用自组装的测试系统评价电池输出性能。结果表明,合成的PSCF粉体呈立方钙钛矿结构,具有良好的氧化–还原可逆性。使用GDC功能层明显改善了氢气环境下PSCF与LSGM材料间的化学相容性以及电池的输出性能,800℃时,电极│电解质界面极化电阻从6.892?·cm^2下降到0.314?·cm^2;以加湿H_2(含体积分数3%的水蒸气)为燃料气,空气为氧化气时,单电池输出功率密度由269 m W/cm2增大至463 m W/cm^2。研究结果显示,PSCF是对称固体氧化物燃料电池良好的候选电极材料,GDC功能层对改善电池长期稳定性能具有潜在的应用价值。展开更多
BaCe0.8Pr0.2O3-α ceramic was synthesized by high temperature solid-state reaction. The structural characteristics and the phase purity of the crystal were determined using powder X-ray diffraction analysis. By using ...BaCe0.8Pr0.2O3-α ceramic was synthesized by high temperature solid-state reaction. The structural characteristics and the phase purity of the crystal were determined using powder X-ray diffraction analysis. By using the methods of AC impedance spectroscopy, gas concentration cell and electrochemical pumping of hydrogen, the conductivity and ionic transport number of BaCe0.8Pr0.2O3-α were measured, and the electrical conduction behavior of the material was investigated in different gases in the temperature range of 500-900℃. The results indicate that the material was of a single perovskite-type orthorhombic phase. From 500℃ to 900 ℃, electronic-hole conduction was dominant in dry and wet oxygen, air or nitrogen, and the total conductivity of the material increased slightly with increasing oxygen partial pressure in the oxygen partial pressure range studied. Ionic conduction was dominant in wet hydrogen, and the total conductivity was about one or two orders of magnitude higher than that in hydrogen-free atmosphere （oxygen, air or nitrogen）展开更多
文摘采用柠檬酸-硝酸盐自蔓延燃烧法分别合成了Pr_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)(PSCF)和Gd_(0.2)Ce_(0.8)O_(2-δ)(GDC)粉体,高温固相法合成La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_(3-δ)(LSGM)电解质粉体。以LSGM为电解质,PSCF同时作为阴极和阳极,GDC作为功能层材料,构建了对称固体氧化物燃料电池PSCF│GDC│LSGM│GDC│PSCF。利用X射线衍射法研究材料的成相以及相互间的化学稳定性,交流阻抗法记录界面极化行为,用扫描电子显微镜观察电池的断面微结构,用自组装的测试系统评价电池输出性能。结果表明,合成的PSCF粉体呈立方钙钛矿结构,具有良好的氧化–还原可逆性。使用GDC功能层明显改善了氢气环境下PSCF与LSGM材料间的化学相容性以及电池的输出性能,800℃时,电极│电解质界面极化电阻从6.892?·cm^2下降到0.314?·cm^2;以加湿H_2(含体积分数3%的水蒸气)为燃料气,空气为氧化气时,单电池输出功率密度由269 m W/cm2增大至463 m W/cm^2。研究结果显示,PSCF是对称固体氧化物燃料电池良好的候选电极材料,GDC功能层对改善电池长期稳定性能具有潜在的应用价值。
基金This work was supported by the National Natural Science Foundation of China （No.20771079） and the Natural Science Foundation of Education Department of Jiangsu Province （No.07KJB150126）.
文摘BaCe0.8Pr0.2O3-α ceramic was synthesized by high temperature solid-state reaction. The structural characteristics and the phase purity of the crystal were determined using powder X-ray diffraction analysis. By using the methods of AC impedance spectroscopy, gas concentration cell and electrochemical pumping of hydrogen, the conductivity and ionic transport number of BaCe0.8Pr0.2O3-α were measured, and the electrical conduction behavior of the material was investigated in different gases in the temperature range of 500-900℃. The results indicate that the material was of a single perovskite-type orthorhombic phase. From 500℃ to 900 ℃, electronic-hole conduction was dominant in dry and wet oxygen, air or nitrogen, and the total conductivity of the material increased slightly with increasing oxygen partial pressure in the oxygen partial pressure range studied. Ionic conduction was dominant in wet hydrogen, and the total conductivity was about one or two orders of magnitude higher than that in hydrogen-free atmosphere （oxygen, air or nitrogen）
