Study on the structure, energy transfer, and color-tunable photoluminescence of the stable BaY2Si3O10: Bi/Tb/Sm phosphors

With the growing concern about energy consumption, white light-emitting diodes( w LEDs), as the fourth generation of lighting sources, are highly scrutinized by researchers. A series of Bi 3+ /Tb 3+ /Sm 3+ (co)doped BaY 2 Si 3 O 10 phosphors were prepared by traditional solid-state method, and the phase purity was analyzed by X-ray diffraction. In this work, Bi 3+ /Tb 3+ /Sm 3+ theoretically occupies the Ba/Y sites, and this conjecture is also proved by spectral analysis. Under near ultraviolet ( n UV) light excitation, Bi 3+ /Tb 3+ /Sm 3+ is respectively used as the blue ( 3 P 1 → 1 S 0 )/green ( 5 D 4 → 7 F j )/red ( 4 G 5/2 → 6 H j ) luminescence center. Due to the energy transfer (ET) efficiency between Bi 3+ /Sm 3+ is not ideal, Tb 3+ is introduced as a bridge to improve the ET efficiency of the whole system to achieve spectral tunability and application in w LEDs. And at different excitation wavelengths, Bi 3+ emits a wide range of blue to cyan light because it occupies two cation sites. We selected a proper excitation wavelength and obtained an emission spectrum covering the whole visible region. The CIE color coordinates (0.3487, 0.3313), the correlated color temperature (CCT, 4773.61 K), quantum efficiency (QE, 47.62 %), and thermal stability ( T 50  = 537 K) of BaY 2 Si 3 O 10 : Bi 3+ /Tb 3+ /Sm 3+ are discussed in depth, Lu 3+ was used instead of Y 3+ to improve the thermal stability of BYS. Its excellent luminescence performance indicates that this phosphor has potential applications in n UV w LEDs.