Preparation, characterizations, and applications for heterometallic-oxides prepared by thermal decomposition of new heteronulear complexes

新型异核配合物热分解制备异金属氧化物的制备、表征及应用

• 批准号: 10650811
• 负责人: SADAOKA Yoshihiko
• 金额: $ 2.24万
• 依托单位: Ehime University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650811/
• 关键词: Heteronuclear complex; Thermal decomposition; Perovskite-type oxide; Fine particle; Gas sensor; NO_2; Surface analysis; 多核複合金属錯体; 超伝導性酸化物; 希土類錯体

Heterometalllic oxides are one of the promising material as electrodes of fuel cells and chemical sensors. We have been proposed the thermal decomposition of heteronuclear complexes as a new method for the preparation of di- or tri-metallic oxides. We found that heterometallic oxides with relatively high specific surface area were formed at low temperatures when heteronuclear hexacyano-complexes were used as precursors. The heteronuclear LaMn(dhbaen)(OH)(NO_3)(H_2O)_4 complex was synthesized and perovskite-type hexagonal LaMnO_3 was obtained by its thermal decomposition at 700 ℃. Particle size of the samples decomposed at 600 ℃ and 700 ℃ is ca. 20 nm and 50 nm, respectively. Furthermore, homogenious La_<1-x>Sm_xFeO_3, NdFe_<0.5>Co_<0.5>O_3, YBa_2Cu_3O_7 tri-metallic oxides were prepared using same method. LaFeO_3 and SmFeO_3 were applied for semiconductor-type NO_2 gas sensors and determined its surface structure using XPS.The number of adsorption sites for the sample prepared by this method was larger than that by solid reaction method. On the other hand, the change of the electrical conductivity for composite La_2CuO_4-CuO was strongly changed by the 10 ppm H_2S gas flow. The reaction of the composite oxide in H_2S gas was investigated to determine its mechanism.

异质金属氧化物是燃料电池电极和化学传感器极具发展前景的材料之一。我们提出了异质核配合物的热分解作为制备二金属或三金属氧化物的新方法。我们发现，以杂核六价配合物为前驱体，在低温下可形成具有较高比表面积的异金属氧化物。合成了异核LaMn(dhbaen)(OH)(NO_3)(H_2O)_4配合物，在700℃下热分解得到钙钛矿型六方LaMnO_3。在600℃和700℃下分解的样品粒径分别约为20 nm和50 nm。用同样的方法制备了La_<1-x>Sm_xFeO_3, NdFe_<0.5>Co_<0.5>O_3， YBa_2Cu_3O_7三金属氧化物。将LaFeO_3和SmFeO_3应用于半导体型NO_2气体传感器，并利用XPS测定了其表面结构。该方法制备的样品的吸附位点数量大于固相反应制备的样品。另一方面，10 ppm H_2S气体流量对La_2CuO_4-CuO复合材料电导率的影响较大。研究了复合氧化物在h2s气体中的反应机理。

项目成果

H.Aono, K.Kinoshita, Y.Sadaoka, M.Sakamoto: "Homogeneity for NdFe_<0.5>Co_<0.5>O_3 Trimetallic Oxide Prepared by Themal Decompsition of Heteronuclear Complexes, Nd[Fe_<0.5>Co_<0.5>(CN)_6]・4H_2O"J.Ceram.Soc.Jpn.. 106(10). 958-963 (1998)

H.Aono、K.Kinoshita、Y.Sadaoka、M.Sakamoto：“通过异核配合物热分解制备 NdFe_<0.5>Co_<0.5>O_3 三金属氧化物的均质性，Nd[Fe_<0.5>Co_<0.5>(CN) )_6]・4H_2O"J.Ceram.Soc.Jpn.. 106(10). 958-963 (1998)

E.Traversa, P.Nunziante, M.Sakamoto, Y.Sadaoka, M.C.Cristina, G.Martinelli: "Thermal Evolution of the Microsrstructure of Nanosized LaFeO_3 Powders from the Thermal Decomposition of a Heteronuclear Complex, La[Fe(CN)_6]・5H_2O"J.Mater.Res.. 13. 1335-1344 (

E.Traversa、P.Nunziante、M.Sakamoto、Y.Sadaoka、M.C.Cristina、G.Martinelli：“异核配合物 La[Fe(CN)_6] 热分解导致纳米 LaFeO_3 粉末微观结构的热演化・5H_2O"J.Mater.Res.. 13. 1335-1344 (

H.Aono, M.Sakamoto, Y.Sadaoka: "Surface Composition and Electrical Conductivity of La_2CuO_4 and CuO Composite on Exposure to ppm Level H_2S"J.Ceram.Soc.Jpn.. 108. 1050-1057 (2000)

H.Aono、M.Sakamoto、Y.Sadaoka：“La_2CuO_4 和 CuO 复合物暴露于 ppm 级 H_2S 时的表面成分和电导率”J.Ceram.Soc.Jpn.. 108. 1050-1057 (2000)

K.サクタイ希土類錯体:

K. Saktai稀土复合体：

E.Traversa,S.Villanti,G.Gusmano,H.Aono,Y.Sadaoka: "Design of Ceramic Materials for Chemical Sensors : SmFeO_3 Thick Films Sensitive to NO_2 "J.Am.Ceram.Soc.. 82. 2442-2450 (1999)

E.Traversa、S.Villanti、G.Gusmano、H.Aono、Y.Sadaoka：“化学传感器陶瓷材料的设计：对 NO_2 敏感的 SmFeO_3 厚膜”J.Am.Ceram.Soc.. 82. 2442-2450