Low-temperature chemical synthesis of lanthanum monoaluminate

Date

1997-01-01

Author

Taspinar, E
Tas, AC

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

183
views

0
downloads

One of the promising candidates for ferroelectric substrate materials, lanthanum monoaluminate (LaAlO3), was successfully synthesized by two separate chemical powder preparation techniques: (i) homogeneous precipitation from aqueous solutions containing urea (CH4N2O) in the presence of nitrate salts, and (ii) self-propagating combustion synthesis from aqueous solutions containing CH4N2O and the respective nitrate salts of lanthanum and aluminum. The submicrometer, spherical-like particles of the precursors were completely converted to pure LaAlO3 at 850 degrees C in the homogeneous precipitation route, and the same conversion temperature was observed to be 750 degrees C, which becomes the lowest temperature ever reported for the powder synthesis of a pure LaAlO3 phase. The materials were characterized by powder X-ray diffractometry, simultaneous thermogravimetric/differential thermal analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Structural refinements by Rietveld analysis showed that LaAlO3 was isostructural with BaTbO3 and had the space group R-3c, in contrast to the previously assumed space group of R-3m for this phase. The atomic positions in the structure of LaAlO3 were refined and presented for the first time, with respect to the present space group.

Subject Keywords

Materials Chemistry, Ceramics and Composites

URI

https://hdl.handle.net/11511/64613

Journal

JOURNAL OF THE AMERICAN CERAMIC SOCIETY

DOI

https://doi.org/10.1111/j.1151-2916.1997.tb02801.x

Collections

Department of Metallurgical and Materials Engineering, Article

Suggestions

OpenMETU
Core

Enhanced methylene blue removal efficiency of TiO2 embedded porous glass Ertus, E. Burak; Vakifahmetoglu, Cekdar; Öztürk, Abdullah (Elsevier BV, 2021-02-01) A porous glass (PG) embedded with titanium dioxide (TiO2) was produced via impregnation of the PG with Titanium (IV) Isopropoxide solution followed by crystallization. N-2 sorption analyses revealed that the specific surface area (SSA) and total pore volume of the PG reached to 358 m(2)/g and 0.370 cm(3)/g, respectively. The adsorption capacity of methylene blue (MB) for the glasses was measured in the dark, instead the photocatalytic MB removal efficiency was evaluated by the degradation of MB under UV lig...
Highly Efficient Room Temperature Synthesis of Silver-Doped Zinc Oxide (ZnO:Ag) Nanoparticles: Structural, Optical, and Photocatalytic Properties Yildirim, Ozlem Altintas; Ünalan, Hüsnü Emrah; Durucan, Caner (Wiley, 2013-03-01) Synthesis of silver-doped zinc oxide (ZnO:Ag) nanoparticles through precipitation method has been reported. The synthesis was conducted at room temperature and no subsequent thermal treatment was applied. ZnO nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), fourier transmission infrared spectroscopy (FTIR), and ultraviolet-visible (UVVis) spectroscopy. Detailed crystallographic investigation was accomplished through ...
Synthesis and Characterization of 2-Hydroxyethyl Methacrylate (HEMA) and Methyl Methacrylate (MMA) Copolymer Used as Biomaterial Vargun, Elif; SANKIR, MEHMET; Aran, Bengi; DEMİRCİ SANKIR, NURDAN; Usanmaz, Ali (Informa UK Limited, 2010-01-01) A series of poly(methyl methacrylate-co-hydroxyethyl methacrylate) (PMMA-co-PHEMA), copolymers were synthesized by an emulsion polymerization technique. Copolymer compositions were determined by FT-IR and 1H-NMR spectroscopy. It was found that comonomer ratios used in the recipes were comparable within the actual copolymers. Glass transition temperatures (Tg) of PMMA-co-PHEMA copolymers were varied from 119 degrees C to 100 degrees C by increasing HEMA content. Thermogravimetric analysis showed that the cop...
The conductive polyaniline/poly(ethylene terephthalate) composite fabrics Kutanis, S.; Karakisla, M.; Akbulut, Ural; Sacak, M. (Elsevier BV, 2007-01-01) Conductive composite fabrics were prepared by chemical polymerization of aniline on poly(ethylene terephthalate) (PET) fabrics in the aqueous hydrochloride acid solutions using potassium dichromate as the oxidant. The effect of the polymerization conditions such as temperature, oxidant, aniline and hydrochloride acid concentrations was investigated on the electrical surface resistance and polyaniline (PAn) content of PAn/PET composite fabrics. The maximum PAn content and the lower electrical resistance of c...
ACTIVITY COMPOSITION RELATIONS IN NIAL2O4-MNAL2O4 SOLID-SOLUTIONS AND STABILITIES OF NIAL2O4 AND MNAL2O4 AT 1300-DEGREES-C AND 1400-DEGREES-C TIMUCIN, M; MUAN, A (Wiley, 1992-06-01) Activities of NiO were measured in the oxide and spinel solutions of the system MnO-NiO-Al2O3 at 1300-degrees and 1400-degrees-C with the aim of deriving information on the thermodynamic properties of the spinel phases. Synthetic samples in selected phase assemblages of the system were equilibrated with metallic nickel and a gas phase of known oxygen partial pressures at a total pressure of 1 atm. The data on NiO activities and directions of conjugation lines between coexisting oxide and spinel phases were ...

Citation Formats

E. Taspinar and A. Tas, “Low-temperature chemical synthesis of lanthanum monoaluminate,” JOURNAL OF THE AMERICAN CERAMIC SOCIETY, pp. 133–141, 1997, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/64613.