A single-component white-light-emitting fluorescent material with high color rendering index based on resonance energy transfer

The development of single-component high-quality warm white light-emitting phosphors is a research hotspot and key in the field of white light illumination. In this paper, a series of Ca8ZnGa0.4La0.6(PO4)(7):xEu(2+),yMn(2+) solid solutions were prepared based on resonance energy transfer to achieve a controlled tuning of the emission color from blue-green to red, and a single-phase white-light-emitting phosphor Ca8ZnGa0.4La0.6(PO4)(7):0.003Eu(2+),0.02Mn(2+) was obtained. The doping of Mn2+ leads to the rearrangement of Eu2+ at different cation positions, while the sensitization effect of different emission peaks of Eu2+ on Mn2+ was inconsistent, and the contribution of the 490 nm emission peak was greater. In addition, the thermal stability properties of the different emission peaks of Eu2+ differed due to different thermal ionization probabilities, and the Mn2+ emission centers showed better thermal stability properties as the non-radiative relaxation between Eu2+ and Mn2+ was enhanced with increasing temperature. Finally, the Ca8ZnGa0.4La0.6(PO4)(7):0.003Eu(2+),0.02Mn(2+) phosphor-converted WLED exhibited a high quality warm white light emission with an ultra-high color rendering index (R-a = 94.7) and a suitable CCT value (4277 K) at an operating current of 300 mA.