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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Structural and spectroscopic properties of phosphate-tungsten glasses doped with Nd3+ and Tb3+

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Autor(es):
Guidini, Priscila [1] ; Galleani, Gustavo [1] ; Faria, Walter [1] ; Silva, Igor D. A. [1] ; Eckert, Hellmut [1, 2] ; de Camargo, Andrea S. S. [1]
Número total de Autores: 6
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Inst Fis Sao Carlos, CP 369, BR-13560970 Sao Carlos, SP - Brazil
[2] Westfalische Wilhelms Univ Munster, Inst Phys Chem, D-48149 Munster - Germany
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: Journal of Non-Crystalline Solids; v. 529, FEB 1 2020.
Citações Web of Science: 0
Resumo

Glasses of composition 90NaPO(3)-10WO(3)-xNd(2)O(3), (0 <= x <= 1.7 mol%) and 90NaPO(3)-10WO(3)-yTbF(3), (0 <= y <= 5.0 mol%) have been prepared and characterized. P-31 and Na-23 magic-angle spinning (MAS) NMR and Na-23[P-31] rotational echo double resonance results are consistent with previously published data, indicating the presence of Q((2)) and Q(1 W)((1)) units. In addition, linear dependences of P-31 MAS-NMR linewidths and spin-lattice relaxation rates and the electron spin-spin relaxation behavior (in the case of Nd2O3 doping) are consistent with a random dopant distribution, For Nd2O3- doped glass samples, absorption spectra in the visible and infrared regions were collected and analysed, and photoluminescence excitation and emission spectra were obtained under 575 nm excitation. Using the Judd-Ofelt formalism, the Omega(2), Omega(4) and Omega(6) parameters were determined and by using them, the radiative lifetime (tau(r)) were calculated for the F-4(3/2) excited state. The fluorescence quantum efficiency value for this level (QE = tau(f)/tau(r)) of 13% was determined for glass with x = 1.0. The photophysical properties of Tb- doped glasses were also studied and upon UV excitation (372 nm) the glasses show emissions in the green (540 nm, D-5(4) -> F-7(5) transition) and blue (434 nm, D-5(3) -> F-7(4)). The relative luminescence intensity ratio D-5(3) -> F-7(5)/D-5(4) -> F-7(5) is higher for lower Tb3+ content (0.5 Tb glass sample), because for higher Tb3+ contents, a cross-relaxation energy transfer process takes place favoring the green emission. (AU)

Processo FAPESP: 18/03931-9 - Preparação de vidros e vitrocerâmicas de fluorofosfatos dopados com íons terras-raras para potencial uso como detectores de radiação.
Beneficiário:Gustavo Galleani
Linha de fomento: Bolsas no Brasil - Pós-Doutorado
Processo FAPESP: 13/07793-6 - CEPIV - Centro de Ensino, Pesquisa e Inovação em Vidros
Beneficiário:Edgar Dutra Zanotto
Linha de fomento: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs