La0.7-xSmx+0.02Ca0.3CrO3-δ (0≤x≤0.4) powders with A-site excessive perovskite structure were synthesized by auto-ignition process and characterized. X-ray diffraction (XRD) patterns of samples after sintering ...La0.7-xSmx+0.02Ca0.3CrO3-δ (0≤x≤0.4) powders with A-site excessive perovskite structure were synthesized by auto-ignition process and characterized. X-ray diffraction (XRD) patterns of samples after sintering at 1400℃ for 4 h were indexed as tetragonal structure. The relative densities were all above 96% although decreased slightly with the increasing content of samarium, indicating that the excessive A-site element was helpful to enhance their sinterability. Conductivities of the specimens in air increased with increasing content of samarium. The conductivity of La0.6Sm0.12Ca0.3CrO3_swas 33.6 S/cm in air at 700℃ which was about 1.7 times as high as that of La0.7Ca0.3CrO3-δ (20.1 S/cm). Average thermal expansion coefficients (TECS) of the specimens increased from 11.06×10^-6 to 12.72×10^-6 K^-1 when x increased from 0 to 0.4, and they were close to that of Y doped ZrO2 (YSZ).La0.7-xSmx+0.02Ca0.3CrO3-δ (0.1≤x≤0.3) were good choices for intermediate temperature solid oxide fuel cells (IT-SOFCs) interconnect materials.展开更多
Solid oxide fuel cells(SOFCs)are an all-solid energy conversion device from the chemical energy of fuels to electric energy at intermediate and high temperatures.Up to now,massive efforts have been made in developing ...Solid oxide fuel cells(SOFCs)are an all-solid energy conversion device from the chemical energy of fuels to electric energy at intermediate and high temperatures.Up to now,massive efforts have been made in developing different components of solid oxide fuel cells,including electrolyte,anode,cathode and interconnect materials.Rare earth elements play an indispensable role in different components of SOFCs which have been extensively studied in the recent decades.In this review,we concentrate upon the rare earth application and recent advances in SOFCs and related materials.Materials structure involves perovskites,Ruddlesden-Popper,fluorite,spinel,pyrochlore,apatite and so on.Moreover,the effects of rare earth based oxides as matrix or dopants in different components are also discussed.Structures and properties of the materials are related to the element type,valence,coordination and ion radius.This article will provide a comprehensive research direction towards SOFCs components for their composition,structural design and mechanisms research.展开更多
基金supported by the National Natural Science Foundation of China (50572099)
文摘La0.7-xSmx+0.02Ca0.3CrO3-δ (0≤x≤0.4) powders with A-site excessive perovskite structure were synthesized by auto-ignition process and characterized. X-ray diffraction (XRD) patterns of samples after sintering at 1400℃ for 4 h were indexed as tetragonal structure. The relative densities were all above 96% although decreased slightly with the increasing content of samarium, indicating that the excessive A-site element was helpful to enhance their sinterability. Conductivities of the specimens in air increased with increasing content of samarium. The conductivity of La0.6Sm0.12Ca0.3CrO3_swas 33.6 S/cm in air at 700℃ which was about 1.7 times as high as that of La0.7Ca0.3CrO3-δ (20.1 S/cm). Average thermal expansion coefficients (TECS) of the specimens increased from 11.06×10^-6 to 12.72×10^-6 K^-1 when x increased from 0 to 0.4, and they were close to that of Y doped ZrO2 (YSZ).La0.7-xSmx+0.02Ca0.3CrO3-δ (0.1≤x≤0.3) were good choices for intermediate temperature solid oxide fuel cells (IT-SOFCs) interconnect materials.
基金Project supported by Fundamental Research Funds for Central Universities of the China University of Geosciences Beijing(590121038)Cultivation Project of the State Key Laboratory of Green Development and High-value Utilization of Ionic Rare Earth Resources in Jiangxi Province(20194AFD44003)。
文摘Solid oxide fuel cells(SOFCs)are an all-solid energy conversion device from the chemical energy of fuels to electric energy at intermediate and high temperatures.Up to now,massive efforts have been made in developing different components of solid oxide fuel cells,including electrolyte,anode,cathode and interconnect materials.Rare earth elements play an indispensable role in different components of SOFCs which have been extensively studied in the recent decades.In this review,we concentrate upon the rare earth application and recent advances in SOFCs and related materials.Materials structure involves perovskites,Ruddlesden-Popper,fluorite,spinel,pyrochlore,apatite and so on.Moreover,the effects of rare earth based oxides as matrix or dopants in different components are also discussed.Structures and properties of the materials are related to the element type,valence,coordination and ion radius.This article will provide a comprehensive research direction towards SOFCs components for their composition,structural design and mechanisms research.