La1-xSrxGa1-y MgyO3-δ(LSGM) electrolyte, La1-xSrxCr1-y MnyO3-δ( LSCM ) anode and La1-xSrxFe1-y MnyO3-aaaaaaa(LSFM) cathode materials were all synthesized by glycine-nitrate process (GNP). The microstructure and char...La1-xSrxGa1-y MgyO3-δ(LSGM) electrolyte, La1-xSrxCr1-y MnyO3-δ( LSCM ) anode and La1-xSrxFe1-y MnyO3-aaaaaaa(LSFM) cathode materials were all synthesized by glycine-nitrate process (GNP). The microstructure and characteristics of LSGM, LSCM and LSFM were tested via X-ray diffraction(XRD), scanning electron microcopy (SEM), A C impedance and four-probe direct current techniques. XRD shows that pure perovskite phase LSGM electrolyte and electrode (LSCM anode and LSFM cathode) materials were prepared after being sintered at 1400℃for 20 h and at 1000℃for 5 h, respectively. The max conductivities of LSGM (ionic conductivity), LSCM (total conductivity) and LSFM (total conductivity) materials are 0.02, 10, 16 S·cm-1 in the air below 850℃, respectively. The conductivity of LSCM becomes smaller when the atmosphere changes from air to pure hydrogen at the same temperature and it decreases with the temperature like metal. The porous and LSGM-based LSCM anode and LSFM cathode films were prepared by screen printing method, and the sintering temperatures for them were 1300 and 1250℃, respectively. LSGM and electrode (LSCM and LSFM) materials have good thermal and chemical compatibility.展开更多
La0.7 Ca0.3 CrO3 powder consisting of superfine and uniform particles ( 100-200 nm ) were synthesized using a glycine-nitrate process ( GNP ). The sintering and electronic conducting properties of La0.7 Ca0.3 CrO3...La0.7 Ca0.3 CrO3 powder consisting of superfine and uniform particles ( 100-200 nm ) were synthesized using a glycine-nitrate process ( GNP ). The sintering and electronic conducting properties of La0.7 Ca0.3 CrO3 were invetigated in the sintering temperature range of 1 200-1 450 ℃. The desired morphology of the powder significantly improved its sinterability. La0.7 Ca0.3 CrO3 ceramics sintered at 1 250-1 450 ℃ show high relative densities above 95 % . The ceramics sintered at 1 250-1 400 ℃ have very similar electronic conduct- ing properties, providing electronic conductivities around 55 Ω^-1 cm^-1 at a measuring temperature of 800 ℃ . Further increasing the sintering temperature to 1450 ℃ led to an apparent degradation of electronic conducting properties. This research demonstrates the advantage of the GNP in producing La0.7 Ca0.3 CrO3 with respect to the enhanced sintering properties and superior electronic conducting properties.展开更多
Sr- and Mg-doped lanthanum gallate powders with the composition of La0.55Sr0.15Ga0.85Mg0.15O2.85were synthesized by a glycine-nitrate combustion method. Powders prepared under different fuel combustion conditions were...Sr- and Mg-doped lanthanum gallate powders with the composition of La0.55Sr0.15Ga0.85Mg0.15O2.85were synthesized by a glycine-nitrate combustion method. Powders prepared under different fuel combustion conditions were investigated by XRD and TEM. The results show that, under slightly rich fuel condition, the product powders contain less impurity phases, and powders prepared by the glycine-nitrate combustion contain far less impurity phases and have smaller particle sizes than those prepared by solid-state reaction method or acrylamide polymerization technique.展开更多
基金Project supported by the National Natural Science Foundation of China (50204007)the Foundation of Yunnan Province (2005PY01-33)
文摘La1-xSrxGa1-y MgyO3-δ(LSGM) electrolyte, La1-xSrxCr1-y MnyO3-δ( LSCM ) anode and La1-xSrxFe1-y MnyO3-aaaaaaa(LSFM) cathode materials were all synthesized by glycine-nitrate process (GNP). The microstructure and characteristics of LSGM, LSCM and LSFM were tested via X-ray diffraction(XRD), scanning electron microcopy (SEM), A C impedance and four-probe direct current techniques. XRD shows that pure perovskite phase LSGM electrolyte and electrode (LSCM anode and LSFM cathode) materials were prepared after being sintered at 1400℃for 20 h and at 1000℃for 5 h, respectively. The max conductivities of LSGM (ionic conductivity), LSCM (total conductivity) and LSFM (total conductivity) materials are 0.02, 10, 16 S·cm-1 in the air below 850℃, respectively. The conductivity of LSCM becomes smaller when the atmosphere changes from air to pure hydrogen at the same temperature and it decreases with the temperature like metal. The porous and LSGM-based LSCM anode and LSFM cathode films were prepared by screen printing method, and the sintering temperatures for them were 1300 and 1250℃, respectively. LSGM and electrode (LSCM and LSFM) materials have good thermal and chemical compatibility.
基金Funded by the Programfor New Century Excellent Talents inUniversity(NCET-04-0724)and Special Research Foundforthe Doc-oral Program of High Education ( No.20030497008) .It is alsorateful to Hubei Province Key Laboratory of Refractories and Ce-amics-Ministry-Province Jointly-Constructed Cultivation Base fortate Key Laboratoryfor Supportingthe Research(No.G0406)
文摘La0.7 Ca0.3 CrO3 powder consisting of superfine and uniform particles ( 100-200 nm ) were synthesized using a glycine-nitrate process ( GNP ). The sintering and electronic conducting properties of La0.7 Ca0.3 CrO3 were invetigated in the sintering temperature range of 1 200-1 450 ℃. The desired morphology of the powder significantly improved its sinterability. La0.7 Ca0.3 CrO3 ceramics sintered at 1 250-1 450 ℃ show high relative densities above 95 % . The ceramics sintered at 1 250-1 400 ℃ have very similar electronic conduct- ing properties, providing electronic conductivities around 55 Ω^-1 cm^-1 at a measuring temperature of 800 ℃ . Further increasing the sintering temperature to 1450 ℃ led to an apparent degradation of electronic conducting properties. This research demonstrates the advantage of the GNP in producing La0.7 Ca0.3 CrO3 with respect to the enhanced sintering properties and superior electronic conducting properties.
文摘Sr- and Mg-doped lanthanum gallate powders with the composition of La0.55Sr0.15Ga0.85Mg0.15O2.85were synthesized by a glycine-nitrate combustion method. Powders prepared under different fuel combustion conditions were investigated by XRD and TEM. The results show that, under slightly rich fuel condition, the product powders contain less impurity phases, and powders prepared by the glycine-nitrate combustion contain far less impurity phases and have smaller particle sizes than those prepared by solid-state reaction method or acrylamide polymerization technique.