Perovskite-Type Lanthanum Cobaltite LaCoO3: Aspects of Processing Route toward Practical Applications

Nanoscale lanthanum cobaltite with perovskite-type was successfully synthesized by microwave irradiation directly and was characterized by XRD, SEM, XPS and BET analysis. The results show that the size of particle was 18 nm averagely, the surface area to be 31.0 m2 g−1. The electrochemical properties were studied by cyclic voltammetry and steady state polarization. The cyclic voltammogram between 0 and 0.55 V exhibited two pairs of redox peaks prior to the onset of O2 evolution in 1 mol dm−3 KOH. The Tafel slope and the reaction order with respect to concentration of OH− were found to be 60 mV decade−1 and ca. 1, respectively.

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Tubular lanthanum cobaltite perovskite type membrane for oxygen permeation

Journal of Membrane Science ◽

10.1016/s0376-7388(99)00244-6 ◽

2000 ◽

Vol 166 (1) ◽

pp. 51-61 ◽

Cited By ~ 52

Author(s):

Shiguang Li ◽

Wanqin Jin ◽

Pei Huang ◽

Nanping Xu ◽

Jun Shi ◽

...

Keyword(s):

Oxygen Permeation ◽

Lanthanum Cobaltite ◽

Perovskite Type

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Effect of thermoelectric material of Ca or Fe-doped LaCoO3

International Journal of Modern Physics B ◽

10.1142/s0217979218400374 ◽

2018 ◽

Vol 32 (19) ◽

pp. 1840037

Author(s):

Kei-Ichiro Murai ◽

Shuhei Kori ◽

Shun Nakai ◽

Toshihiro Moriga

Keyword(s):

Figure Of Merit ◽

Solid Phase ◽

X Ray Diffraction ◽

Lanthanum Cobaltite ◽

Iron Doped ◽

Calcium Doped ◽

Diffraction Patterns ◽

Lanthanum Cobalt Oxide ◽

Perovskite Type ◽

Fe Substitution

As the Perovskite-type Lanthanum Cobalt Oxide of LaCoO3 is nontoxic and thermally stable even at high temperature, this material is expected as a candidate for thermoelectric applications. The thermoelectric performance of a material is often evaluated by the dimensionless figure-of-merit, ZT (=S[Formula: see text]T/[Formula: see text]), or S[Formula: see text] in the ZT equation. S[Formula: see text] shows the electrical characteristic as a Power factor (PF). It has been reported Seebeck coefficient of LaCoO3 is higher than other oxide materials at room temperature even though electrical conductivity and ZT are lower values. In this study, calcium-doped lanthanum cobaltite La[Formula: see text]Ca[Formula: see text]CoO3 (x = 0.00, 0.05, 0.10 and 0.15) and iron-doped lanthanum cobaltite LaCo[Formula: see text]Fe[Formula: see text]O3 (y = 0.05, 0.10 and 0.15) have been prepared by solid-phase process. The X-ray diffraction patterns of the calcium-doped samples and iron-doped samples show cubic perovskite structure. Electric conductivities were improved by Ca or Fe substitution and showed a tendency to increase with increasing the temperature. The sample substituted with Fe 5 mol.% showed the maximum PF, 0.510 ([Formula: see text] W/K2m) at 548 K, and the sample substituted with Ca 15 mol.% showed the maximum PF, 0.152 ([Formula: see text] W/K2m) at 498 K.

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Tubular lanthanum cobaltite perovskite-type membrane reactors for partial oxidation of methane to syngas

Journal of Membrane Science ◽

10.1016/s0376-7388(99)00245-8 ◽

2000 ◽

Vol 166 (1) ◽

pp. 13-22 ◽

Cited By ~ 98

Author(s):

Wanqin Jin ◽

Shiguang Li ◽

Pei Huang ◽

Nanping Xu ◽

Jun Shi ◽

...

Keyword(s):

Partial Oxidation ◽

Partial Oxidation Of Methane ◽

Membrane Reactors ◽

Lanthanum Cobaltite ◽

Oxidation Of Methane ◽

Perovskite Type

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Preparation of Non-Oxide Ceramics by Pyrolysis of Organometallic Precursors

MRS Proceedings ◽

10.1557/proc-271-739 ◽

1992 ◽

Vol 271 ◽

Cited By ~ 8

Author(s):

Leonard V. Interrante ◽

Wayde R Schmidt ◽

Paul S. Marchetti ◽

Gary E. Maciel

Keyword(s):

Ceramic Materials ◽

Ceramic Fiber ◽

High Yield ◽

Processing Route ◽

Chemical Processing ◽

Practical Applications ◽

Fiber Technology ◽

Organometallic Molecules ◽

Organometallic Precursors ◽

Yield And Purity

Chemical processing routes to advanced ceramic materials are gaining importance as a convenient approach to control the stoichiometry, purity, microstructure and final form of the ceramic products [1]. The pyrolytic conversion of organometallic molecules and polymers is one such chemical processing route that has been widely applied in ceramic fiber technology [1,2], in coating processes [1,2], and in the sintering of bulk ceramic objects [3]. Despite these advances in practical applications, there is a continuing need in this area for a better fundamental understanding of the chemistry involved during the precursor-to-ceramic conversion process and for the development of new precursors which yield the desired ceramic(s) in high yield and purity.

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Structural investigation of the cubic perovskite-type doped lanthanum cobaltite La0.6Sr0.4CoO3−δat 1531 K: possible diffusion path of oxygen ions in an electrode material

Journal of Applied Crystallography ◽

10.1107/s0021889807048637 ◽

2007 ◽

Vol 40 (6) ◽

pp. 1166-1168 ◽

Cited By ~ 24

Author(s):

Masatomo Yashima ◽

Takayuki Tsuji

Keyword(s):

Oxygen Deficiency ◽

Diffusion Path ◽

Atomic Displacement ◽

Ion Migration ◽

Lanthanum Cobaltite ◽

Oxygen Ions ◽

Density Mapping ◽

Neutron Powder Diffraction Data ◽

Atomic Displacement Parameters ◽

Perovskite Type

The crystal structure of a cubic Pm\overline 3 m perovskite-type doped lanthanum cobaltite, La0.6Sr0.4CoO3−δ, has been studied usingin situneutron powder diffraction data measured at 1531 K. The refined occupancy 0.886 (6) of O atoms at the 3d1/2, 0, 0 site indicated an oxygen deficiency of δ = 0.34 (2) and an average valence of +2.7 for Co cations in La0.6Sr0.4CoO3−δat 1531 K. Refined anisotropic atomic displacement parameters and nuclear density mapping reveal that the oxygen ions in La0.6Sr0.4CoO3−δexhibit a large thermal motion perpendicular to the Co—O bond. A curved path for oxygen-ion migration between adjacent anion sites in La0.6Sr0.4CoO3−δis proposed, although it was not observed as a connected density in the experimental mapping.

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