Energy transfer behavior and tunable spectroscopic properties of Ba3Lu4O9:Dy3+,Eu3+ phosphors for white LEDs

Ba3Lu4O9:Dy3+,Eu3+ phosphors were developed through the conventional solid-state reaction. Luminescent performance including the energy transfer from dysprosium to europium, spectral tunability, fluorescent lifetime and thermal quenching behavior of the as-studied phosphors was studied. The characteristic emission of Dy3+ and Eu3+ were detected in Ba3Lu4O9:Dy3+,Eu3+ upon the excitation at various ultraviolet–visible wavelengths. The critical distance between dysprosium and europium ions was evaluated to be about 16.05 Å. The energy transfer from dysprosium to europium in Ba3Lu4O9 can be attributed to the dipole-quadruple mechanism, and the efficiency was evaluated to be 81.8% for Ba3Lu3.52O9:0.16Dy3+,0.32Eu3+. The tunable warm-white emission and high thermal stability reveal that the as-studied phosphor can be an auspicious alternative for white LEDs application.