Structural and spectroscopic characterization of Al2-xCrxO3 powders obtained by polymeric precursor method
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Data
2007-07-01
Autores
Cava, Sergio
Beninca, Renata
Tebcherani, Sergio M.
Souza, Iedo A.
Paskocimas, Carlos A.
Longo, Elson [UNESP]
Varela, José Arana [UNESP]
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Editor
Springer
Resumo
Al2O3 and Al2-x Cr (x) O-3 (x = 0.01, 0.02 and 0.04) powders have been synthesized by the polymeric precursors method. A study of the structural evolution of crystalline phases corresponding to the obtained powders was accomplished through X-Ray Diffraction and UV-vis spectroscopy (reflectance spectra and CIEL* a*b* color data). The obtained results allow to identify the gamma-Al2O3 to alpha-Al2O3 phase transition. The single-phase alpha-Al2O3 powder was obtained after heat treatment at 1050 degrees C for 2 h. The results show that the green to red color transition and ruby luminescence lines observed for the powders of Al2-x Cr (x) O-3 are related to the gamma to alpha-Al2O3 phase transition and the temperature and time range for such transition depends on the chromium content.
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Al2O3, Al2-xCrxO3, phase transition, powder synthesis, spectroscopy, polymeric precursor method
Como citar
Journal of Sol-gel Science and Technology. Dordrecht: Springer, v. 43, n. 1, p. 131-136, 2007.