Red-emitting SrGe4O9:Eu3+ phosphors obtained by combustion synthesis
Por:
Garcia, C. R., Oliva, J., Garcia-Lobato, M. A., Martinez, A. I., Ochoa-Valiente, R., Hirata, G. A.
Publicada:
15 oct 2017
Resumen:
In this work, red-emitting Strontium-Germanate SrGe4O9:xEu(3+) (SGO)
phosphors doped with x = 0%, 1%, 3% and 5 at% of Eu were obtained by
a combustion method. The X-ray diffraction patterns of these phosphors
revealed that all the samples have a trigonal phase. Morphological
studies by scanning electron microscopy (SEM) showed irregular coalesced
grains that formed with sizes in the range of 0.14-0.22 pm. Furthermore,
the degree of coalescence among particles increased as the content of Eu
dopant augments. The optical band gap (Es) of pure and Eu-doped SGO were
calculated with Tauc plots and was observed a decrease of Es as the Eu
concentration increases. Also, the emission spectra of Eu-doped SGO
(under UV excitation at 303 nm) revealed that their luminescence
centered at 611 nm increased as the Eu content is raised, with a maximum
luminescence was observed for the sample doped with 3 at% of Eu.
Finally, the CIE (Commission Internationale de l'Eclairage) chromaticity
coordinates of (0.56, 0.34) were calculated for the sample with the
highest luminescence, which did not change even for Eu concentrations as
high as 5 at%. Due to their intense red emission and stability for CIE
coordinates, SrGe4O9:xEu(3+) phosphors could be good candidates for the
generation of the red component in solid state lighting devices.
Filiaciones:
Garcia, C. R.:
Univ Autonoma Coahuila, Fac Ciencias Fisicomatemat, Prol David Berlanga S-N, Saltillo 25000, Coahuila, Mexico
Oliva, J.:
Univ Autonoma Coahuila, Fac Ciencias Fisicomatemat, Prol David Berlanga S-N, Saltillo 25000, Coahuila, Mexico
Univ Autonoma Coahuila, Fac Ciencias Quim, CONACYT, Ing J Cardenas Valdez, Saltillo 25280, Coahuila, Mexico
Garcia-Lobato, M. A.:
Univ Autonoma Coahuila, Fac Ciencias Quim, CONACYT, Ing J Cardenas Valdez, Saltillo 25280, Coahuila, Mexico
Martinez, A. I.:
Inst Politecn Nacl, Unidad Saltillo, Ctr Invest & Estudios Avanzados, Ind, Ramos Arizpe 25900, Coah, Mexico
Ochoa-Valiente, R.:
Univ Autonoma Coahuila, Fac Ciencias Fisicomatemat, Prol David Berlanga S-N, Saltillo 25000, Coahuila, Mexico
Hirata, G. A.:
UNAM, Ctr Nanociencias & Nanotecnol, Km 107 Carretera Tij Ens, Ensenada 22860, Baja California, Mexico
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