[en] A series of new emission-tunable phosphors Bi_0.95−yPO₄:0.05Tb³⁺,yEu³⁺ were synthesized by a facile hydrothermal method with surfactant-free environment. XRD results indicated that phosphors possess the standard BiPO₄ monoclinic structure. From the luminescence spectra and decay curves, the energy transfer from Tb³⁺ to Eu³⁺ was confirmed. The efficient Tb³⁺ to Eu³⁺ energy transfer can be used to tune the emission color from green, yellow to orange by simply changing the concentration of europium, making the materials have potential applications in three-color-based displays and white light illumination. Finally, the energy transfer mechanism between Tb³⁺ and Eu³⁺ was demonstrated to be the electric quadrupole–quadrupole interaction based on Dexter's energy transfer formula and the Inokuti–Hirayama model. - Highlights: • BiPO₄: Tb³⁺, Eu³⁺ phosphor was synthesized by a facile hydrothermal method. • Energy transfer from Tb³⁺ to Eu³⁺ in BiPO₄ was firstly studied. • The Q–Q interaction is the main mechanism for energy transfer from Tb³⁺ to Eu³⁺. • BiPO₄: Tb³⁺, Eu³⁺ has potential applications in white LEDs and display devices

[en] Highlights: • Lager increases in the emission have been achieved by doping Y³⁺ in Li₂CaSiO₄:Eu²⁺. • The enhancement mechanism is due to the increase number of Eu²⁺ with Y³⁺ doping. • Li₂CaSiO₄:Eu²⁺,Y³⁺ is useful for phosphor converted white LEDs and display devices. • Li₂CaSiO₄:Eu²⁺,Y³⁺has higher emission intensity than BAM upon 375 nm excitation. - Abstract: Y³⁺ doped Li₂CaSiO₄:Eu²⁺ phosphors were synthesized by the solid state reaction method. Lager increases in the emission have been achieved by doping Y³⁺ in the host. Upon 375 nm excitation, the present synthesized phosphors have higher emission intensity than that of the commercial blue phosphor, BaMgAl₁₀O₁₇:Eu²⁺. The doping effects of Y³⁺ were discussed systematically based on the analysis of structure, morphology, element, and spectroscopic properties. XRD patterns and EDS spectrum revealed that the samples maintained Li₂CaSiO₄ phase after doping Eu²⁺ and Y³⁺. SEM images showed the morphology and particle size of all phosphors were similar. DRS showed doping Y³⁺ could enhance the absorption of Li₂CaSiO₄:Eu²⁺. Finally, the enhancement mechanism was studied in detail. It was also observed that the emission of Li₂CaSiO₄:Eu²⁺ could also be enhanced by doping other rare earth ions RE³⁺ (RE = Dy, Er, Sm, Tm, Tb, and Yb), which could confirm the mechanism. These results provided a useful basis for further improving the luminescence performance of silicate phosphors