A novel luminescence material of emitting color-tunable Ca20Al26Mg3Si3O68 (denoted as CAMSO):Ce3+,Tb3+ phosphors have been synthesized via the high temperature solid-phase reaction process. The crystal cell structure, photoluminescence properties and application performance such as thermal stability and LED device performance of the phosphors were researched in detail. CAMSO:Ce3+,Tb3+ phosphors showed multicolor with the different concentration of Ce3+ and Tb3+ ions. Although the concentration of Ce3+ ions was settled and there was the existence of energy transfer from Ce3+ to Tb3+ ions, it was found that Ce3+ ions’ blue light emission intensity showed abnormal increasing with the increase of Tb3+ ions doping concentration. The irregular phenomenon was discussed in detail. The phosphor CAMSO:0.2Ce3+,0.1Tb3+ photoluminescence emission intensity motivated by 374 nm at 150 °C retained about 81% of that measured at room temperature, which demonstrating the good thermal and color stability of the sample. In addition, the white LED lamps were fabricated through mixing the sample CAMSO:0.2Ce3+,0.2Tb3+ and the commercial phosphor CaAlSiN3:Eu2+ and their performance has been measured. The results show that this series of phosphors could be excellent candidates for the application of UV-excited w-LEDs.

The emission hue can be tuned from cool white to white, and finally to warm white light due to the energy transfer from Bi3+ ions to Sm3+ ions. Simultaneously, two kinds of sites for cations (Ca2+) in the host were considered.

A series of emission-tunable YF3:RE3+ (RE = Dy, Tb, Eu) phosphors were first synthesized by a glutamic acid-assisted one-step hydrothermal process. The structure and morphology were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results revealed that the samples were YF3 and Na­(Y1.5Na0.5)­F6 and the size and shape of the products could be tuned just by adjusting the pH values of the initial reaction solutions or by adjusting the RE3+/NaF ratio or RE3+/NaBF4 ratio. The morphologies for the products include bundlelike microstructures, fantail-like shape, microspindles, irregular bulk, walnutlike shape, irregular ellipsoidal microrods, the asymmetric hexagonal-prismatic tubular structures and irregular microrods and irregular nanoparticles and microsphere. Furthermore, the photoluminescence properties of YF3:Dy3+,Tb3+ and YF3:Tb3+,Eu3+ were investigated in detail. Blue and yellow emissions corresponding to the 4F9/2 → 6H15/2 (475 nm), 4F9/2 → 6H13/2 (570 nm) transition of Dy3+; blue and green emissions corresponding to the 5D4 → 7F6 (488 nm), 5D4 → 7F5 (542 nm) transition of Tb3+; and red emissions corresponding to the 5D0 → 7F1 (591 nm), 5D0 → 7F2 (614 nm), and 5D0 → 7F4 (698 nm) transition of Eu3+ can be observed in YF3 host under 365 nm near-ultraviolet radiation. The energy transfer process from Dy3+ to Tb3+ and from Tb3+ to Eu3+ was demonstrated to be resonant type via a quadrupole–quadrupole mechanism. Additionally, when codoping Tb3+ with Dy3+ or Eu3+ or tridoping Dy3+, Tb3+, and Eu3+ ions in the single component, colorful emitting can be obtained, giving abundant blue, green, yellow, orange, and especially white light emission. The temperature-dependent photoluminescence for as-prepared phosphors has been investigated in detail. Importantly, it is found that the fluorescent intensity ratio of YF3:5%Dy3+,2%Tb3+,2%Eu3+ displays a linear correlation with temperature in the wide range of 298–398 K with a high sensitivity of 0.24% K–1, indicating that it could be a good candidate for ratiometric optical thermometry. All these properties indicate that the developed phosphor may potentially be used as single-component multicolor-emitting phosphors.

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