Highly efficient and thermally robust single-component white-emitting Ca3LuAl3B4O15:Bi3+,Tb3+,Eu3+ phosphors for UV LEDs

Single-component white phosphor is highly desirable to obtain efficient and stable white light-emitting diodes (w-LED). In this paper, a series of Bi3+, Tb3+, and Eu3+ doped Ca3LuAl3B4O15 (CLAB) luminescent materials were successfully prepared. The structure, morphology, and optical properties of samples were characterized by X-ray diffractometer, scanning electronic microscopy, and fluorescence spectroscopy, respectively. The synthesized phosphor exhibits strong blue band emission from Bi3+ and intense characteristics line emission from Tb3+ and Eu3+ under ultraviolet (UV) light excitation. The emission color can fine be adjusted by changing the doping content of the three activators. The warm white light of CLAB:0.5%Bi3+,2%Tb3+,0.75%Eu3+ with CIE chromaticity coordinates of (0.3728,0.3166), a CCT of 3671 K, and a Ra index of 87 could be realized under UV light excitation. The fabricated w-LED by combining UV chip with CLAB:0.5%Bi3+,2%Tb3+,0.75%Eu3+ shows excellent thermal stability after high-temperature aging test, implying its promising application in single-phosphor-converted warm w-LEDs.