Nd3+ doped new oxyfluoro tellurite glasses and glass ceramics containing NaYF4 nano crystals-1.06 mu m emission analysis

Autor(es)

Rajesh, Dagupati ^{[1, 2]} ; de Camargo, A. S. S. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sao Carlos Inst Phys, POB 369, BR-13560970 Sao Carlos, SP - Brazil

^[2] Alexander Dubcek Univ Trencin, Ctr Funct & Surface Functionalized Glass, Trencin - Slovakia

• Tipo de documento: Artigo Científico
• Fonte: Journal of Luminescence; v. 207, p. 469-476, MAR 2019.
• Citações Web of Science: 2

Resumo

Oxyfluoro tellurite glasses with chemical composition TeO2-ZnO-YF3-NaF (TZYN), doped with Nd3+ in different concentrations were prepared by the melt-quenching technique. Judd-Ofelt analyses of Nd3+ ions in the precursor glasses were performed to evaluate the phenomenological intensity parameters Omega(2,4,6). From the NIR emission spectra, characteristic parameters such as effective band with (Delta lambda(eff)) and stimulated emission cross section (sigma(p)) were calculated for the three observed transitions, F-4(3/2) -> I-4(9/2), I-4(11/2) and I-4(13/2) and compared to other reported glasses. Based on the luminescence decay times of F-4(3/2) excited state, the quantum efficiency was evaluated and it is highest for a 0.2 mol% Nd3+ doped glass (G-Nd2). Glass ceramics were obtained by controlled heat treatment of the glasses at 390 degrees C for 5 h (as determined by DSC), which is greater than the glass transition temperature T-g. Moreover, DSC results revealed that precipitation of the NdYF4 nanocrystalline phase (TC1) decreased with increasing Nd3+ concentration. X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) investigations reveal that spherical NaYF4 nano-crystals are distributed homogeneously across the glassy matrix. The emission intensity of the F-4(3/2) -> I-4(11/2) transition at 1.60 mu m was enhanced in glass ceramics as compared to glasses because of the occupancy of the Nd3+ in NaYF4 nanocrystlline phase. The experimental lifetime value of F-4(3/2) also enhanced from 124 to 187 mu s from G-Nd2 glass to GC-Nd2 glass ceramic and decreased with increasing Nd3+ concentration. (AU)

• 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
• Processo FAPESP: 15/10713-0 - Investigações de conversão ascendente e descendente de energia em vidros e vitrocerâmicas de telúritos dopados com íons terras raras, para aplicações em células solares
• Beneficiário: Rajesh Dagupati
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado