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A series of single Ce3+doped and Ce3+and Tb3+co-doped Na2BaCa(PO4)2(NBCP) phosphors was synthesized by conventional solid-stated reaction method. The crystal structure, luminescence properties, thermal stability and energy transfer were carefully investigated. Ce3+is inferred to substitute the Ba2+site in NBCP lattice. The color-tunable emission from blue to green is observed by adjusting Tb3+concentration among NBCP:0.03Ce3+,yTb3+phosphors. The energy transfer behavior from Ce3+to Tb3+ions is both illustrated by co-doped PL spectra and decay curves. The energy transfer efficiency is as high as 91.5%. The mechanism of energy transfer is resonance type of dipole-dipole transition. In this work, the optimal phosphor exhibits the excellent thermal stability which keeps at 94.9% of that initial value at room temperature when temperature reaches to 150 °C. The Ce3+and Tb3+co-doped NBCP phosphor is a promising candidate for the application in the general lighting and display fields.

Investigating the phosphors doped with single activators in a single component to realize white-light emission is urgently desired for phosphor-converted white-light-emitting diodes. In this work, on the basis of the chemical unit cosubstitution strategy, the new borophosphate phosphors Ba3CaK(PO4)3–x(BO3)x:0.02Eu2+with a mixed anion group were prepared. Coupling structure refinement and photoluminescence analyses, Ba3CaK(PO4)3–x(BO3)xconsists of five different cationic sites with different coordination environments, with Eu2+occupying the three sites for Ba2+. In the process of partial substituting (BO3)3–for (PO4)3–, because of the greatly distorted coordination field generated from the difference in the geometric configurations between the two anion groups, a red shift and broadening of the emission bands occurs, resulting in a color-adjustable emission from blue to white. A phosphor-converted light-emitting diode has been successfully fabricated with the incorporation of an as-prepared Ba3CaK(PO4)2.6(BO3)0.4:0.02Eu2+phosphor and a 405 nm near-ultraviolet chip, which exhibits Commission International de I’Eclairage chromaticity coordinates of (0.31, 0.37) and a correlated color temperature of 6295 K. As demonstrated in the present work, an approach adopted from phosphate to borophosphate is conducted to develop high-quality phosphors.