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

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: ⁶P_7/2–⁸S_7/2 emission in UV range and the Sm³⁺:⁴G_5/2 –⁶H_J luminescence at 598 nm were observed upon the excitation of Gd:4f level by λ_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.