Valéria Rejane Silva Brito, Laboratory for Researching and Innovation of Advanced Materials,Department of Technologic and Exact Sciences State University of Santa Cruz, 45662-900, Ilhéus-Bahia, Brazil

Raquel Jovita dos Santos, Laboratory for Researching and Innovation of Advanced Materials,Department of Technologic and Exact Sciences State University of Santa Cruz, 45662-900, Ilhéus-Bahia, Brazil

Paulo Neilson Marques dos Anjos, Laboratory for Researching and Innovation of Advanced Materials,Department of Technologic and Exact Sciences State University of Santa Cruz, 45662-900, Ilhéus-Bahia, Brazil

Abstract
Calcium aluminate was synthesized doped with trivalent cerium ions (Ce3+) by gel process with ethylene diamine tetraacetic acid (EDTA) as a chelating agent and was doped with trivalent praseodymium ions (Pr3+). Calcium aluminates with praseodymium 1.0% and 0.5% were synthesized. The synthesized material was characterized by means of thermogravimetry and differential thermal analysis and fluorescence spectroscopy and by scanning electron microscopy. Calcium aluminates doped with praseodymium ion that showed less porosity in its grain structure and luminescent transitions that are dependent on the wavelengths of excitation and showing both types of transitions both 5d-4f and 4f-4f. Also, calcium aluminate was obtained by combustion mixing of aluminum, calcium and cerium nitrates, with the respective organic compound used as fuel, glycine or sucrose, in quantity of moles calculated according to the stoichiometry of the redox reaction, with the values of the proportions total nitrate/fuel 1:1.5 for used in the synthesis of glycine and 1:0.2 for used fuel sucrose. The amounts of Ce3+ ions in molar concentrations were 0.25%, 0.5% and 1%. By fluorescence spectroscopy was observed emission bands at 390nm and 415nm related transitions of Ce+3 ion and 650nm related to electronic transitions in the matrix defects.

Keywords
calcium aluminate; cerium phosphor; praseodymium phosphors; thermogravimetry

Cite this paper
Valéria Rejane Silva Brito, Raquel Jovita dos Santos, Paulo Neilson Marques dos Anjos, Morphological and Thermal and optical characterizations of the cerium and praseodymium co-doped calcium aluminates obtained by the gel using ethylenediaminetetraacetic acid and by the combustion with glycine and sucrose methods , SCIREA Journal of Chemistry. Volume 1, Issue 1, October 2016 | PP. 16-30.

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