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Ca9La(PO4)5(SiO4)F2:Tb3+,Dy3+ (CLPSF:Tb3+,Dy3+) phosphors were successfully prepared using the traditional solid‐state technique. The crystal structure was refined and the luminescence properties have been examined in detail. The band gap and electronic structure of Ca9La(PO4)5(SiO4)F2 were performed by the periodic density functional theory (DFT) calculation. The spectral and fluorescence decay dynamics of CLPSF:Tb3+,Dy3+ show that the energy transfer behavior between Tb3+ and Dy3+ ions is observed. The CLPSF:Tb3+,Dy3+ phosphors can be efficiently excitable at the wavelengths range from 300 to 500 nm. The emission spectrum covers the whole visible part of the spectra with the sharp emission bands in red, green, and blue regions. The correlated color temperature (CCT) and color rendering index (CRI) of white light emission could be improved by the fine‐tuning of the Tb3+ and Dy3+ ions ration in accordance with the energy transfer behavior. Thus, the CLPSF:Tb3+,Dy3+ phosphor could be used as a material for the near‐ultraviolet (n‐UV) and white light‐emitting diodes (w‐LEDs). [ABSTRACT FROM AUTHOR]

Single-phase KLaSr3( PO4)3F: Sm3+ phosphors with fluorapatite structure were prepared via high-temperature solid-state method in air atmosphere for the first time. The X-ray diffraction, scanning electron microscope, diffuse reflectance spectra, photoluminescence spectra, and temperature-dependent emission spectra, as well as lifetimes were measured to characterize the as-prepared phosphors. Phase results indicated that KLaSr3( PO4)3F: Sm3+ belongs to hexagonal system with a space group of P-6. Photoluminescence measurements showed the emission spectrum was composed of four sharp peaks at about 564, 602 (the strongest one), 646, and 702 nm, corresponding to the 4G5/2-6 H J ( J=5/2, 7/2, 9/2, and 11/2) transitions of Sm3+ ions. The optimum doping concentration of Sm3+ ions was turned out to be 0.03 (mol), and the mechanism of energy transfer among Sm3+ ions was considered to be dipole-dipole interaction by using Dexter's theory. In addition, the critical distance Rc for energy transfer among Sm3+ ions were calculated to be 9.97 Å according to Blasse concentration quenching method. The selected KLa0.97Sr( PO4)3F: 0.03Sm3+ exhibited high thermal stability with an activation energy of 0.163 eV. Besides, the Commission International de l'Eclairage chromaticity coordinate of the phosphor were located in the orange-reddish light region. [ABSTRACT FROM AUTHOR]