Porous NiO-Ce0.8Sm0.2O1.9（NiO-SDC） ceramics with homogeneous pore distribution were prepared using polystyrene （PS） spheres as pore templates. NiO-SDC powders were synthesized by a glycine-nitrate method, ultrason...Porous NiO-Ce0.8Sm0.2O1.9（NiO-SDC） ceramics with homogeneous pore distribution were prepared using polystyrene （PS） spheres as pore templates. NiO-SDC powders were synthesized by a glycine-nitrate method, ultrasonically mixed with PS spheres in ethanol, dried and then pressed into green pellets. The pellets were sintered to yield porous NiO-SDC ceramics. The effects of the sintering temperature on the microstructure and mechanical strength of the ceramics were investigated. NiO-SDC ceramics sintered at 1200 and 1350℃ have interconnected pore structures and high compression strength. When single cells were fabricated using porous NiO-SDC ceramics as anode-supported layers, the peak power density of the cells at 600℃ was 333 and 353 mW.cm-2 for ceramics sintered at 1200 and 1350℃, respectively. The results indicated that these porous ceramic materials are promising for anode substrates for solid oxide fuel cells.展开更多
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
NiO and Ce0.8Sm0.2O1.9 were synthesized by the combination of sol gel and citric acid-nitrate low temperature self-propagating combustion method. Anode precursors which include home-made NiO and Ce0.8Sm0.2O1.9 were pr...NiO and Ce0.8Sm0.2O1.9 were synthesized by the combination of sol gel and citric acid-nitrate low temperature self-propagating combustion method. Anode precursors which include home-made NiO and Ce0.8Sm0.2O1.9 were prepared by different NiO content and fabrication condition. The anode precursors with pure hydrogen at 820 ℃ for 2.5 h were reduced, The electrical conductivity was tested, and the effect of microstructure on electrical conductivity of Ce0.8Sm0.2O1.9 composite anodes was investigated. The results show that the anode electrical conductivity depends strongly on the anode microstructure that is dramatically affected by Ni content and fabrication condition.展开更多
基金supported by the Zhejiang Provincial Natural Science Foundation of China (No.Y4080307)the research fund of Shenzhen Key Laboratory of Functional Polymers
文摘Porous NiO-Ce0.8Sm0.2O1.9（NiO-SDC） ceramics with homogeneous pore distribution were prepared using polystyrene （PS） spheres as pore templates. NiO-SDC powders were synthesized by a glycine-nitrate method, ultrasonically mixed with PS spheres in ethanol, dried and then pressed into green pellets. The pellets were sintered to yield porous NiO-SDC ceramics. The effects of the sintering temperature on the microstructure and mechanical strength of the ceramics were investigated. NiO-SDC ceramics sintered at 1200 and 1350℃ have interconnected pore structures and high compression strength. When single cells were fabricated using porous NiO-SDC ceramics as anode-supported layers, the peak power density of the cells at 600℃ was 333 and 353 mW.cm-2 for ceramics sintered at 1200 and 1350℃, respectively. The results indicated that these porous ceramic materials are promising for anode substrates for solid oxide fuel cells.
文摘应用溶胶-凝胶法制备了Ce_(0.8)Sm_(0.2)O_(1.9)固体电解质粉体,通过X射线衍射对所制备的电解质粉体进行了物相分析。研究表明,Sm2O3已经固溶到CeO_2中形成了具有萤石结构CeO_2基固溶体。经成型并在1450℃下烧结2 h获得致密的Ce_(0.8)Sm_(0.2)O_(1.9)固体电解质。通过组装含有氧离子阻塞电极电池(-)致密Al2O3,Pt|Ce_(0.8)Sm_(0.2)O_(1.9)(SDC)固态电解质|Pt,O2(+)测试空气中不同温度下的电子电导。应用扫描电子显微镜观察所制备试样的微观组织形貌,结果表明:制备的电解质组织致密,高温粘合剂、电解质及刚玉坩埚结合紧密,保证了阻塞电极的气密性。采用Hebb-Wagner离子阻塞电极法测定了Ce_(0.8)Sm_(0.2)O_(1.9)在空气气氛下的电子导电性。结果显示:在测量温度范围内Ce_(0.8)Sm_(0.2)O_(1.9)固体电解质的电子电导率在1×10-8~1×10-6m S·cm-1之间,经计算得出活化能的平均值为0.9885 e V。
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NiO and Ce0.8Sm0.2O1.9 were synthesized by the combination of sol gel and citric acid-nitrate low temperature self-propagating combustion method. Anode precursors which include home-made NiO and Ce0.8Sm0.2O1.9 were prepared by different NiO content and fabrication condition. The anode precursors with pure hydrogen at 820 ℃ for 2.5 h were reduced, The electrical conductivity was tested, and the effect of microstructure on electrical conductivity of Ce0.8Sm0.2O1.9 composite anodes was investigated. The results show that the anode electrical conductivity depends strongly on the anode microstructure that is dramatically affected by Ni content and fabrication condition.
