Ce0.8Sm0.2O1.9-δ-La0.9Sr0.1Ga0.8Mg0.2O3-δ（SDC-LSGM）is prepared by the glycine-nitrate process（GNP）.SDC-LSGM composite electrolyte samples with different weight ratios are prepared by the co-combustion method so ...Ce0.8Sm0.2O1.9-δ-La0.9Sr0.1Ga0.8Mg0.2O3-δ（SDC-LSGM）is prepared by the glycine-nitrate process（GNP）.SDC-LSGM composite electrolyte samples with different weight ratios are prepared by the co-combustion method so as to obtain homogeneous nano-sized precursor powders. The X-ray diffraction （XRD） and the scan electron microscope （SEM） are used to investigate the phases and microstructures. The measurements and analyses of oxygen ionic conductivity of SDC-LSGM are carried out through the four-terminal direct current （DC） method and the electrochemical impendence spectroscopy, respectively. The optimum weight ratio of SDC-LSGM is 8∶2, of which the ionic conductivity is 0.113 S/cm at 800℃ and the conductivity activation energy is 0.620 eV. The impendence spectra shows that the grain boundary resistance becomes the main barrier for the ionic conductivity of electrolyte at lower temperatures. The appropriate introduction of LSGM to the electrolyte SDC can not only decrease the electronic conductivity but also improve the conditions of the grain and grain boundary, which is advantageous to cause an increase in oxygen ionic conductivity.展开更多
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
基金The National Basic Research Program of China (973 Program) (No.2007CB936300)the Natural Science Foundation of Jiangsu Province (No.BK2009293)
文摘Ce0.8Sm0.2O1.9-δ-La0.9Sr0.1Ga0.8Mg0.2O3-δ（SDC-LSGM）is prepared by the glycine-nitrate process（GNP）.SDC-LSGM composite electrolyte samples with different weight ratios are prepared by the co-combustion method so as to obtain homogeneous nano-sized precursor powders. The X-ray diffraction （XRD） and the scan electron microscope （SEM） are used to investigate the phases and microstructures. The measurements and analyses of oxygen ionic conductivity of SDC-LSGM are carried out through the four-terminal direct current （DC） method and the electrochemical impendence spectroscopy, respectively. The optimum weight ratio of SDC-LSGM is 8∶2, of which the ionic conductivity is 0.113 S/cm at 800℃ and the conductivity activation energy is 0.620 eV. The impendence spectra shows that the grain boundary resistance becomes the main barrier for the ionic conductivity of electrolyte at lower temperatures. The appropriate introduction of LSGM to the electrolyte SDC can not only decrease the electronic conductivity but also improve the conditions of the grain and grain boundary, which is advantageous to cause an increase in oxygen ionic conductivity.
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。
