Gd3+/Sm3+ energy transfer behavior and spectroscopic study of lithium gadolinium magnesium borate for solid state lighting material

초록

We report the luminescence and energy transfer features in (B2O3)(0.55-x)(Li2O)(0.30) (MgO)(0.10)(Gd2O3)(0.05) (Sm2O3)(x) glasses, prepared via melt-quenching rout. By employing the Judd-Ofelt (JO) theory, the spectral parameters such as oscillator strengths, stimulated emission cross-sections, radiative transition probability and branching ratios are evaluated from the absorption and emission spectra. The dipole-dipole interaction as a dominant interaction mechanism is confirmed from Inokuti-Hirayama (IH) model. The luminescent color falls in the orange part of commission International de I'Eclaiage (CIE). The ultra-violet (UV) sensitization of visible emission of Sm3+ is analyzed by the photoluminescence (PL) emission spectra and the lifetime measurement. The Gd: (6)P7/S-2-8(7/2) emission in UV range and the Sm3+:(4)G(5/2) (-6)HJ luminescence at 598 nm were observed upon the excitation of Gd:4f level by lambda(exc) = 275 nm. Moreover, the impact of energy transfer on the donor-acceptor luminescence, quantum efficiency, and donor luminescence decay kinetics are investigated. It is found that efficient orange luminescence originates from Sm3+ emitting centers. These findings show that these as-prepared luminescent glasses are promising in orange LEDs and laser applications.

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