Wydział Chemii

Łukasz Marek

Marcin Sobczyk

2018

Journal of Non-Crystalline Solids

487

96-103

10.1016/j.jnoncrysol.2018.02.005

Naukowa

Angielski

Artykuł

Tellurite glasses of the composition xPr₆O₁₁–(7 − x)La₂O₃–3Na₂O–25ZnO–65TeO₂ (where x = 0.005, 0.01, 0.1, 0.2, 0.5, 1.0 and 2 mol%) were obtained by the melt quenching technique. Absorption (300 K), excitation (300 K) and fluorescence spectra (at 77 and 300 K) as well as fluorescence decay curves of the Pr³⁺-doped title glasses are presented and discussed. Basing on the Judd-Ofelt analysis, the phenomenological Judd-Ofelt parameters (Ω₂ = 2.13, Ω₄ = 16.8 and Ω₆ = 3.50 × 10⁻²⁰ cm²), radiative transition probabilities (A_T), branching ratios (β), radiative lifetimes (τ_R) and emission cross-sections (σ_em) were calculated for the luminescence from ³P₁, ³P₀, ¹D₂ and ¹G₄ levels of the Pr³⁺ ion. The fluorescence from the ¹G₄ level of the Pr³⁺ ion has been observed after excitation at 445 nm in the ³P₂ state. The experimental lifetimes of the emission levels indicate strong concentration quenching. An analysis of non-radiative decay of the ¹D₂ level indicate that energy migration via a diffusion limited relaxation and cross-relaxation processes are involved in the depopulation of this level. The spectroscopic results show that the investigated glasses are potentially candidates as at 1.3 μm and 1.45 μm laser host as well as reddish-orange to yellow tunable phosphor. Furthermore, a near-infrared downconversion process gives possibility of using of these materials as luminescent solar concentrators and near infrared lasers.

Pr3+, Tellurite glasses, luminescence, Quantum cutting, energy transfer, laser materials

http://doi.org/10.1016/j.jnoncrysol.2018.02.005

http://www.elsevier.com