Photoluminescence behavior of the Sm3+ and Tb3+ ions doped into the Gd2(WO4)3 matrix prepared by the Pechini and ceramic methods
| العنوان: | Photoluminescence behavior of the Sm3+ and Tb3+ ions doped into the Gd2(WO4)3 matrix prepared by the Pechini and ceramic methods |
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| المؤلفون: | G. E. S. Brito, Hermi F. Brito, Cláudia A. Kodaira, Ercules E.S. Teotonio, Maria C.F.C. Felinto, Oscar L. Malta |
| المصدر: | Journal of the Brazilian Chemical Society, Volume: 15, Issue: 6, Pages: 890-896, Published: DEC 2004 Journal of the Brazilian Chemical Society v.15 n.6 2004 Journal of the Brazilian Chemical Society Sociedade Brasileira de Química (SBQ) instacron:SBQ |
| بيانات النشر: | Sociedade Brasileira de Química, 2004. |
| سنة النشر: | 2004 |
| مصطلحات موضوعية: | Materials science, Photoluminescence, terbium, Analytical chemistry, chemistry.chemical_element, Infrared spectroscopy, Terbium, General Chemistry, Ion, chemistry.chemical_compound, Pechini and ceramic methods, Tungstate, chemistry, tungstate, photoluminescence, Emission spectrum, samarium, Luminescence, Europium |
| الوصف: | The Gd2(WO4)3:RE3+ compounds (where RE3+ = Sm and Tb) were prepared by the Pechini and ceramic methods and characterized by X-ray diffraction and infrared spectroscopy. These rare earth materials present high orange (Sm3+-compound) and green (Tb3+-compound) luminescence intensity under UV radiation. The excitation spectra of these compounds presented broad bands arising from ligand-to-metal charge transfer (O->W and O->RE3+) and narrow bands from 4f-intraconfigurational transitions. The excitation spectra of Tb3+ system also exhibit broad bands attributed to the interconfigurational transition (4f-5d). The emission spectra exhibited the 4G5/2->6H J (J = 5/2, 7/2, 9/2 and 11/2) and 5D4-> 7F J (J = 0-6) transitions (direct excitation), for the systems doped with Sm3+ and Tb3+, respectively, while a broad band assigned to the LMCT (O->W) is observed when the excitation is monitored on the O->W LMCT state around 270 nm. The experimental intensity parameters etaSm and etaEu present similar behaviors, suggesting that the Sm3+ ion is in a highly polarizable chemical environment with similar covalent character of the metal-donor atom interaction to the tungstate doped europium system. The cross-relaxation process from the 5D3 to the 5D4 levels of the Gd2(WO4)3:Tb3+ system has been also reported. Os compostos Gd2(WO4)3:RE3+ (onde RE = Sm e Tb) preparados via métodos Pechini e cerâmico foram caracterizados por difratometria de raios-X e espectroscopia de absorção na região do infravermelho. Estes materiais de terras raras apresentam alta intensidade luminescente, laranja para os compostos de Sm3+ e verde para os de Tb3+, quando excitados com radiação UV. Os espectros de excitação dos compostos mostraram bandas largas oriundas da transferência de carga ligante-metal (O->W e O->RE3+) e bandas estreitas associadas às transições intraconfiguracionais (4f-4f). Os espectros de excitação do sistema com Tb3+ também exibiram bandas largas atribuídas à transição interconfiguracional (4f-5d). Quando os espectros de emissão dos compostos contendo Sm3+ e Tb3+ são obtidos com excitação no íon observa-se somente transições finas 4G5/2->6H J (J = 5/2, 7/2, 9/2 e 11/2) e 5D4-> 7F J (J = 0-6). Por outro lado, quando a excitação é monitorada na banda de transferência de carga (BTC, 270 nm) são também observadas bandas largas atribuídas a BTC (O->W). Os parâmetros de intensidade experimentais, etaSm e etaEu, apresentaram comportamentos similares, sugerindo que o íon Sm3+ encontra-se em um ambiente químico altamente polarizável e que o caráter covalente da interação metal-ligante é semelhante àquele do sistema tungstato de európio. O processo de relaxação cruzada baseado nos níveis 5D3 e 5D4 do sistema Gd2(WO4)3:Tb³ foi reportado. |
| وصف الملف: | text/html |
| اللغة: | English |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f1f566a1bd0674bdd4de3b8f5b6aca0d http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532004000600016&lng=en&tlng=en |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....f1f566a1bd0674bdd4de3b8f5b6aca0d |
| قاعدة البيانات: | OpenAIRE |
| الوصف غير متاح. |