Ba2Ca(B3O6)2:Eu2+,Mn2+: A potential tunable blue–white–red phosphors for white light-emitting diodes

The Ba2Ca(B3O6)2:Eu2+,Mn2+ borates phosphors were synthesized by a solid state reaction method. The obtained phosphors exhibit a tunable color emission from blue to white and finally to red under an ultraviolet (UV) source by adjusting the ratio of Eu2+ and Mn2+ appropriately. The energy transfer from Eu2+ to Mn2+ in Ba2Ca(B3O6)2:Eu,Mn phosphors was demonstrated to be a resonance type via a dipole–quadrupole mechanism, and the critical distance was estimated to be 9.92 Å. The optimal composition of Ba2Ca(B3O6)2:0.04Eu2+,0.12Mn2+ generates warm white light with chromaticity coordinates (0.37, 0.25) and color temperature of 2654 K, indicating that Ba2Ca(B3O6)2:Eu,Mn phosphor would be a good candidate for white light-emitting diodes (LEDs) applications, especially indoors illumination.