选择具有双钙钛矿结构的Sr2Fe Nb O6(SFN)及La0.9Sr0.1Ga0.8Mg0.2O3-δ(LSGM)材料混合作为固体氧化物电解池(SOEC)的阴极,在SFN-LSGM中掺杂不同比例的淀粉,经过干压成型并在1400℃下烧结后得到测试样。利用真实密度仪及阿基米德法测定...选择具有双钙钛矿结构的Sr2Fe Nb O6(SFN)及La0.9Sr0.1Ga0.8Mg0.2O3-δ(LSGM)材料混合作为固体氧化物电解池(SOEC)的阴极,在SFN-LSGM中掺杂不同比例的淀粉,经过干压成型并在1400℃下烧结后得到测试样。利用真实密度仪及阿基米德法测定了样品的孔隙率;利用热分析仪测定了不同孔隙率的样品在35~1400℃条件下的热膨胀系数,研究该材料与常用SOEC电解质材料La0.9Sr0.1Ga0.8Mg0.2O3-δ(LSGM)的热匹配性能;之后利用电化学工作站测试了该材料在纯氢气气氛下电导率与孔隙率的关系。结果表明,样品孔隙率与淀粉掺杂量成正比,孔隙率对该材料热膨胀系数影响不大,且该材料与LSGM电解池热匹配性能良好。另外,当样品孔隙率增加时,该材料在850℃纯氢气气氛下的电导率在18%孔隙率时达到最大值。展开更多
La0.15Sr0.85Ga0.3Fe0.7O3-δ (LSGFO) and La0.15Sr0.85Co0.3Fe0.7O3-δ (LSCFO) mixed oxygenion and electron conducting oxides were synthesized by using a combined EDTA and citrate complexing method, and the corresponding...La0.15Sr0.85Ga0.3Fe0.7O3-δ (LSGFO) and La0.15Sr0.85Co0.3Fe0.7O3-δ (LSCFO) mixed oxygenion and electron conducting oxides were synthesized by using a combined EDTA and citrate complexing method, and the corresponding dense membranes were fabricated. The properties of the oxide powders and membranes were characterized with combined SEM, XRD, H2-TPR, O2-TPD techniques, mechanical strength and oxygen permeation measurement. The results showed that LSGFO had much higher thermochemical stability than LSCFO due to the higher valence stability of Ga3+. After the temperature-programmed reduction by 5% H2 in Ar from 20°C to 1020°C, the basic perovskite structure of LSGFO was successfully preserved. LSGFO also favors the oxygen vacancy formation better than LSCFO. Oxygen permeation measurement demonstrated that LSGFO had higher oxygen permeation flux than LSCFO, but they had similar activation energy for oxygen transportation, with a value of 110 and 117 kJ · mol-1, respectively. The difference in oxygen permeation fluxes was correlated with the difference in oxygen vacancy concentrations for the two materials.展开更多
文摘选择具有双钙钛矿结构的Sr2Fe Nb O6(SFN)及La0.9Sr0.1Ga0.8Mg0.2O3-δ(LSGM)材料混合作为固体氧化物电解池(SOEC)的阴极,在SFN-LSGM中掺杂不同比例的淀粉,经过干压成型并在1400℃下烧结后得到测试样。利用真实密度仪及阿基米德法测定了样品的孔隙率;利用热分析仪测定了不同孔隙率的样品在35~1400℃条件下的热膨胀系数,研究该材料与常用SOEC电解质材料La0.9Sr0.1Ga0.8Mg0.2O3-δ(LSGM)的热匹配性能;之后利用电化学工作站测试了该材料在纯氢气气氛下电导率与孔隙率的关系。结果表明,样品孔隙率与淀粉掺杂量成正比,孔隙率对该材料热膨胀系数影响不大,且该材料与LSGM电解池热匹配性能良好。另外,当样品孔隙率增加时,该材料在850℃纯氢气气氛下的电导率在18%孔隙率时达到最大值。
基金Acknowledgements This work was supported by the National Natural Science Foundation of China (Grant No. 59789201), the National Advanced Materials Committee of China (Grant No. 715-006-0122) and the Ministry of Science and Technology, China (Grant No. G1
文摘La0.15Sr0.85Ga0.3Fe0.7O3-δ (LSGFO) and La0.15Sr0.85Co0.3Fe0.7O3-δ (LSCFO) mixed oxygenion and electron conducting oxides were synthesized by using a combined EDTA and citrate complexing method, and the corresponding dense membranes were fabricated. The properties of the oxide powders and membranes were characterized with combined SEM, XRD, H2-TPR, O2-TPD techniques, mechanical strength and oxygen permeation measurement. The results showed that LSGFO had much higher thermochemical stability than LSCFO due to the higher valence stability of Ga3+. After the temperature-programmed reduction by 5% H2 in Ar from 20°C to 1020°C, the basic perovskite structure of LSGFO was successfully preserved. LSGFO also favors the oxygen vacancy formation better than LSCFO. Oxygen permeation measurement demonstrated that LSGFO had higher oxygen permeation flux than LSCFO, but they had similar activation energy for oxygen transportation, with a value of 110 and 117 kJ · mol-1, respectively. The difference in oxygen permeation fluxes was correlated with the difference in oxygen vacancy concentrations for the two materials.