Synthesis and characteristics of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} ceramics for cathode materials of SOFC

Title: Synthesis and characteristics of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} ceramics for cathode materials of SOFC

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Abstract

The fine powders of cathode materials with composition La{sub 1{minus}x}Sr{sub x}MnO{sub 3} (x = 0--0.6) for solid oxide fuel cells (SOFC) were prepared by the buffer solution method. TG-DTA was applied to study the formation of perovskite oxide and the sintering behavior of strontium-doped lanthanum manganite powders. The crystal structure and morphology of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} were observed by XRD, SEM and TEM. The high-temperature electrical conductivity was measured by the four-probe method. It was indicated that the formation temperature of perovskite-type La{sub 1{minus}x}Sr{sub x}MnO{sub 3} decreased with the increase of Sr content. The La{sub 1{minus}x}Sr{sub x}MnO{sub 3} display three lattice types at room temperature: orthorhombic (0{<=}x{<=}0.15), hexagonal (0.15 {<=} x {<=} 0.45) and cubic (x{>=}0.45). As x increased, the primary cell volume of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} decreased, and an abrupt decline was found around the phase-transformation point. Results showed that the electrical conductivity of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} was influenced remarkably by the content of Sr, the peak value of 200s/cm was located at x = 0.5 (at 1,273 K in air).

Authors:

Zhong-Tai, Z; Lin, O; Zi-Long, T ^[1]

Tsinghua Univ., Beijing (China). Dept. of Materials Science and Engineering

Publication Date:: 1995-12-31

OSTI Identifier:: 242503

Report Number(s):: CONF-950683-
ISBN 1-56677-095-5; TRN: IM9626%%331

Resource Type:: Conference

Resource Relation:: Conference: 4. international symposium on solid oxide fuel cells, Yokohama (Japan), 18-23 Jun 1995; Other Information: PBD: 1995; Related Information: Is Part Of Proceedings of the fourth international symposium on solid oxide fuel cells (SOFC-IV). Proceedings Volume 95-1; Dokiya, M. [ed.] [National Inst. of Materials and Chemical Research, Tsukuba, Ibaraki (Japan)]; Yamamoto, O. [ed.] [Mie Univ., Tsu, Mie (Japan)]; Tagawa, H. [ed.] [Yokohama National Univ., Yokohama, Kanagawa (Japan)]; Singhal, S.C. [ed.] [Westinghouse Electric Corp., Pittsburgh, PA (United States)]; PB: 1188 p.

Country of Publication:: United States

Language:: English

Subject:: 30 DIRECT ENERGY CONVERSION; 36 MATERIALS SCIENCE; SOLID ELECTROLYTE FUEL CELLS; CATHODES; LANTHANUM OXIDES; SYNTHESIS; CRYSTAL STRUCTURE; ELECTRIC CONDUCTIVITY; STRONTIUM OXIDES; MANGANESE OXIDES; THERMAL GRAVIMETRIC ANALYSIS; DIFFERENTIAL THERMAL ANALYSIS; X-RAY DIFFRACTION; SCANNING ELECTRON MICROSCOPY; TRANSMISSION ELECTRON MICROSCOPY; ACTIVATION ENERGY

Citation Formats


                    Zhong-Tai, Z, Lin, O, and Zi-Long, T. Synthesis and characteristics of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} ceramics for cathode materials of SOFC.  United States: N. p., 1995. 
        Web.

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                    Zhong-Tai, Z, Lin, O, & Zi-Long, T. Synthesis and characteristics of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} ceramics for cathode materials of SOFC.  United States.

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                    Zhong-Tai, Z, Lin, O, and Zi-Long, T. Sun .  
        "Synthesis and characteristics of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} ceramics for cathode materials of SOFC".  United States.

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@article{osti_242503,

  title        = {Synthesis and characteristics of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} ceramics for cathode materials of SOFC},

  author       = {Zhong-Tai, Z and Lin, O and Zi-Long, T},

  abstractNote = {The fine powders of cathode materials with composition La{sub 1{minus}x}Sr{sub x}MnO{sub 3} (x = 0--0.6) for solid oxide fuel cells (SOFC) were prepared by the buffer solution method. TG-DTA was applied to study the formation of perovskite oxide and the sintering behavior of strontium-doped lanthanum manganite powders. The crystal structure and morphology of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} were observed by XRD, SEM and TEM. The high-temperature electrical conductivity was measured by the four-probe method. It was indicated that the formation temperature of perovskite-type La{sub 1{minus}x}Sr{sub x}MnO{sub 3} decreased with the increase of Sr content. The La{sub 1{minus}x}Sr{sub x}MnO{sub 3} display three lattice types at room temperature: orthorhombic (0{<=}x{<=}0.15), hexagonal (0.15 {<=} x {<=} 0.45) and cubic (x{>=}0.45). As x increased, the primary cell volume of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} decreased, and an abrupt decline was found around the phase-transformation point. Results showed that the electrical conductivity of La{sub 1{minus}x}Sr{sub x}MnO{sub 3} was influenced remarkably by the content of Sr, the peak value of 200s/cm was located at x = 0.5 (at 1,273 K in air).},

  doi          = {},

  url          = {https://www.osti.gov/biblio/242503},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {1995},

  month        = {12}

}

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