Effect of the A-site cation on methane oxidation of perovskite-type (La{sub 1-x}M{sub x})CoO{sub 3} (M=Ca, Sr, and Ba)
- Graduate School of Natural Science and Technology (Science), Okayama University, 3-1-1 Tsushima-Naka, Kita-Ku, Okayama 700-8530 (Japan)
- Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyo-Tanabe 610-0321 (Japan)
Perovskite-type (La{sub 1-x}M{sub x})CoO{sub 3} (M=Ca, Sr, and Ba) synthesized at 700 Degree-Sign C in air using the polymerizable complex method had a rhombohedral perovskite-type structure in the range of x{<=}0.06. The oxygen content of the samples was 2.98-2.99, and the specific surface area was 3.5-8.3 m{sup 2}/g regardless of the M ion or x. The Rietveld method indicated that the Co-O distance was also constant regardless of the M ion or x, and that the Co-O-Co angle between two CoO{sub 6} octahedra increased with an increase in the ionic radius of the M ion. The temperature corresponding to the 50% conversion (T{sub 1/2}) of CH{sub 4} oxidation was almost constant for the samples with x=0.04, while the T{sub 1/2} of the samples with x=0.06 was linearly lowered with increases in the ionic radius of the M ion. - Graphical abstract: The conversion from CH{sub 4} to CO{sub 2} and H{sub 2}O on (La{sub 0.94}M{sub 0.06})CoO{sub 3} (M=Ca, Sr, and Ba). Highlights: Black-Right-Pointing-Pointer (La{sub 1-x}M{sub x})CoO{sub 3} (M=Ca, Sr, and Ba) was synthesized using the polymerizable complex method. Black-Right-Pointing-Pointer The Co-O distance was constant regardless of the M ion or x. Black-Right-Pointing-Pointer The Co-O-Co angle increased with an increase in the ionic radius of the M ion. Black-Right-Pointing-Pointer CH{sub 4} oxidation started above 300 Degree-Sign C and finished at 700 Degree-Sign C. Black-Right-Pointing-Pointer The catalytic activity increased with increases in the ionic radius of the M ion.
- OSTI ID:
- 22012140
- Journal Information:
- Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Vol. . 190; ISSN 0022-4596; ISSN JSSCBI
- Country of Publication:
- United States
- Language:
- English
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