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Rare earth ion doped fluorescent powder, as a key material for the application of white light-emitting diodes (w-LEDs), green components often face the problem of poor thermal stability. Developing fluorescent powders with excellent thermal stability is of great significance. This article synthesized a series of Gd 5 Si 2 BO 13 :Tb3+ blue phosphors and non rare earth Bi3+ ion doped Gd 5 Si 2 BO 13 :Tb3+ green phosphors using a high-temperature solid-phase method. The phase structure and photoluminescence characteristics of the sample were analyzed in detail through XRD, excitation and emission spectra, as well as attenuation curves. The energy transfer from Bi3+ to Tb3+ was studied and confirmed through photoluminescence spectra and lifetime decay curves. Research has shown that the addition of Bi3+ significantly enhances the emission intensity of Tb3+ in the near ultraviolet range, and tunes the emission color of Gd 5 Si 2 BO 13 :Bi3+ and Tb3+ from blue to green, attributed to the energy transfer from Bi3+ to Tb3+. In addition, the addition of Bi3+ increased the thermal stability of single doped fluorescent powder Gd 5 Si 2 BO 13 :0.55Tb3+ from 88.21 % to 92.82 % at 150 °C, proving that the Gd 5 Si 2 BO 13 :Bi3+ and Tb3+ samples have good thermal stability. This study not only deepens our understanding of the new main material Gd 5 Si 2 BO 13 , but also provides a reference for the development of green phosphors with excellent thermal stability. [Display omitted] • A series of Gd 5 Si 2 BO 13 :Bi3+, Tb3+ phosphors were successfully synthesized. • The co-doped Gd 5 Si 2 BO 13 :Bi3+, Tb3+ phosphors have excellent emission intensity and thermal stability. • The Gd 5 Si 2 BO 13 :Bi3+, Tb3+ green phosphors is promising for use in high-power LED lighting devices and backlight displays. [ABSTRACT FROM AUTHOR]

Abstract A single-component white-emitting phosphor Sr 9 La(PO 4) 5 (SiO 4)F 2 :Dy3+ pumped for n -UV-light emitting diodes was firstly presented by solid state method and the crystal structures, luminescence properties, especially the concentration quenching behaviors were discussed in detail. Accordingly, the quantum efficiencies as well as lifetime studies of Dy3+ in CLPGF phosphor were also carried out. The results revealed that the Sr 9 La(PO 4) 5 (SiO 4)F 2 :Dy3+ phosphor could be efficiently excited in a broad wavelength ranging near ultraviolet (n -UV) regions, which matched perfectly with n -UV white light emitting diodes (w -LEDs) chips. Under the excitation at 349 nm, the phosphor exhibited three prominent emission peaks in the visible wavelength region located at 483, 578 and 670 nm, which is ascribed to the 4F 9/2 -6H 15/2 , 4F 9/2 -6H 13/2 and 4F 9/2 -6H 11/2 transitions of Dy3+, respectively. It was also proved that the dipole-dipole interactions results in the concentration quenching in Sr 9 La(PO 4) 5 (SiO 4)F 2 :Dy3+ phosphors. Fascinatingly, when the temperature turned up to 150 °C, the emission intensity at 483 and 578 nm was 83.4 and 89.1% of the initial value at room temperature. Additional, the corresponding activation energy Δ E was determined to be 0.16999 and 0.17451 eV, which indicated the excellent thermal stability of the samples. All these findings demonstrated that as-prepared phosphors could act as a high-performance candidate for the application. Highlights • A single-component white-emitting phosphor has been successfully prepared. • As-prepared phosphor has good thermal stability and luminescence efficiency. • The structural data of Sr 9 La(PO 4) 5 (SiO 4)F 2 :Dy3+ is firstly reported. [ABSTRACT FROM AUTHOR]

The Sr 2 La 8 (SiO 4 ) 6 O 2 :Ce 3+ powder phosphor with apatite structure has been successfully synthesized via a facile route of sol-combustion technique. X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and photoluminescence (PL) spectroscopy were used to characterize the as-prepared samples. Sr 2 La 8 (SiO 4 ) 6 O 2 :Ce 3+ phosphor was composed of particles with average sizes range about 300 nm. The phosphor exhibited an absorption ranging from 220 to 390 nm in ultraviolet range and a broad blue-violet emission band peaked at 403 nm with a CIE coordinates of (0.167, 0.028). The concentration quenching mechanism was also determined to be dipole–dipole interaction. [ABSTRACT FROM AUTHOR]