| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 7907606 | Optical Materials | 2018 | 5 Pages |
Abstract
This paper reports structural and luminescence properties of Eu-doped CaAl2O4 produced by an alternative sol-gel method using coconut water. Results of differential thermal analysis (DTA), thermogravimetric analysis (TGA), and X-ray diffraction (XRD) allowed us to identify the best synthesis conditions for sample preparation. Simultaneous measurements of X-ray absorption spectroscopy (XAS) and X-ray excited optical luminescence (XEOL) were also performed in the X-ray energy range of the Eu LIII edge. Results from photoluminescence (PL) showed only the characteristic Eu3+ emission. However, radioluminescence emission spectra from Eu-doped CaAl2O4 shows a process of conversion of Eu3+ to Eu2+, which is induced by X-ray irradiation and is dependent on the radiation dose energy. X-ray absorption near edge structure (XANES) measurements corroborate Eu reduction due to irradiation, showing that only the Eu3+ ion is present in stable form in the CaAl2O4.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Manassés A. Gomes, Jéssica C. Carvalho, Adriano B. Andrade, Marcos V. Rezende, Zélia S. Macedo, Mário E.G. Valerio,