研究了固体氧化物燃料电池Sr_(2)Fe Mo_(0.6)Mg_(0.25)Al_(0.15)O_(6) (SFMMA)双钙钛矿阳极的晶体缺陷结构、热膨胀性能、电荷传输特性、氧化还原稳定性以及电化学性能。结果表明:SFMMA室温下为I 4/m四方结构,400℃时材料转变为F m 3 m...研究了固体氧化物燃料电池Sr_(2)Fe Mo_(0.6)Mg_(0.25)Al_(0.15)O_(6) (SFMMA)双钙钛矿阳极的晶体缺陷结构、热膨胀性能、电荷传输特性、氧化还原稳定性以及电化学性能。结果表明:SFMMA室温下为I 4/m四方结构,400℃时材料转变为F m 3 m立方结构。SFMMA材料的实际晶体结构式为Sr_(2)(Fe_(0.75)Mg_(0.25))(Mo_(0.6)Fe_(0.25)Al_(0.15))O6-δ,材料晶格中含有大量反位缺陷FeB’以及—Fe_(B)—O—Fe_(B’)—键,有利于氧空位的形成及氧离子的迁移扩散。SFMMA的热膨胀系数在25~400℃和400~900℃范围内分别为13.0×10^(–6)K^(–1)和17.6×10^(–6)K^(–1),在氢气气氛下600~900℃温度范围内电导率超过35 S·cm^(–1),并且具有较快的氧表面交换特性以及非常优异的氧化还原循环结构稳定性。在900,850,800℃和750℃时,湿润H_(2)(3%H_(2)O,50 m L/min)气氛中,SFMMA/La_(0.4)Ce_(0.6)O_(2)(LDC)/La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(0.2)O_(3)(LSGM)/LDC/SFMMA对称半电池面比电阻分别为0.096,0.142,0.239Ω·cm^(2)和0.447Ω·cm^(2)。以SFMMA为阳极组装电解质支撑型单电池SFMMA/LDC/LSGM (300μm)/Pr Ba_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5)+δ,850℃时电池最大功率密度可达886 m W·cm^(–2)。展开更多
The double reversible transformations at low temperature in CuZnAlMnNi shape memory alloy were investigated by differential scanning calorimetry. It is found that the transformations occur not only in the as quenched ...The double reversible transformations at low temperature in CuZnAlMnNi shape memory alloy were investigated by differential scanning calorimetry. It is found that the transformations occur not only in the as quenched sample, but also in the as trained, as aged and as thermal cycled samples, and various treatments give rise to different influences on the transformation temperatures of the two transformations. Though the temperature interval between the two transformation peaks increases after training, aging and thermal cycling, the initial temperature of the M → A transformation is just the final temperature of the X → M transformation, namely, the X → M transformation is immediately followed by the M → A transformation upon heating.展开更多
文摘研究了固体氧化物燃料电池Sr_(2)Fe Mo_(0.6)Mg_(0.25)Al_(0.15)O_(6) (SFMMA)双钙钛矿阳极的晶体缺陷结构、热膨胀性能、电荷传输特性、氧化还原稳定性以及电化学性能。结果表明:SFMMA室温下为I 4/m四方结构,400℃时材料转变为F m 3 m立方结构。SFMMA材料的实际晶体结构式为Sr_(2)(Fe_(0.75)Mg_(0.25))(Mo_(0.6)Fe_(0.25)Al_(0.15))O6-δ,材料晶格中含有大量反位缺陷FeB’以及—Fe_(B)—O—Fe_(B’)—键,有利于氧空位的形成及氧离子的迁移扩散。SFMMA的热膨胀系数在25~400℃和400~900℃范围内分别为13.0×10^(–6)K^(–1)和17.6×10^(–6)K^(–1),在氢气气氛下600~900℃温度范围内电导率超过35 S·cm^(–1),并且具有较快的氧表面交换特性以及非常优异的氧化还原循环结构稳定性。在900,850,800℃和750℃时,湿润H_(2)(3%H_(2)O,50 m L/min)气氛中,SFMMA/La_(0.4)Ce_(0.6)O_(2)(LDC)/La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(0.2)O_(3)(LSGM)/LDC/SFMMA对称半电池面比电阻分别为0.096,0.142,0.239Ω·cm^(2)和0.447Ω·cm^(2)。以SFMMA为阳极组装电解质支撑型单电池SFMMA/LDC/LSGM (300μm)/Pr Ba_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5)+δ,850℃时电池最大功率密度可达886 m W·cm^(–2)。
文摘The double reversible transformations at low temperature in CuZnAlMnNi shape memory alloy were investigated by differential scanning calorimetry. It is found that the transformations occur not only in the as quenched sample, but also in the as trained, as aged and as thermal cycled samples, and various treatments give rise to different influences on the transformation temperatures of the two transformations. Though the temperature interval between the two transformation peaks increases after training, aging and thermal cycling, the initial temperature of the M → A transformation is just the final temperature of the X → M transformation, namely, the X → M transformation is immediately followed by the M → A transformation upon heating.
