Narrow-band cyan and green dual-peak emission Rb2KNa(Li3SiO4)4: Eu2+ phosphor for full-spectrum w-LED: Synthesis, structure, and spectrum regulation.

Full-spectrum white LED (w-LED) lighting is primarily achieved through the combination of multiple-color phosphors excited by the chip, and making the development of efficient multi-color phosphors based on single matrix is an excellent choice for full-spectrum w-LED. In this paper, a series of Rb 2 KNa(Li 3 SiO 4) 4 : xEu2+ (0.1 % ≤ x ≤ 15 %) phosphors were successfully synthesized via high-temperature solid-state reaction with varied Eu2+ concentration. At low doping concentration, the Eu2+ ions exhibit primarily green emission at 530 nm in the phosphor. However, as the doping concentration of Eu2+ ions increase, the emission spectrum undergoes a significant transformation. A cyan emission occurs at 478 nm, resulting in the spectral conversion from a green single-peak emission to a dual-peak emission of cyan and green. The spectral conversion is attributed to the changes in the positioning of Eu2+ ions within the crystal lattice. The obtained phosphors demonstrate excellent thermal stability and can be utilized in w-LED devices. After encapsulation with a blue LED chip, it achieves a color rendering index of 91.8 and a correlated color temperature of 4085 K, showcasing its significant application value in the field of full-spectrum w-LED. • By adjusting the doping concentration of Eu2+ ions and occupied lattice position, the emission spectrum of the Rb 2 KNa(Li 3 SiO 4) 4 : xEu2+ (0.1 % ≤ x ≤ 15 %) phosphor was regulated from a single-peak emission of 530 nm (green) to a dual-peak emission of 478 nm (cyan) and 530 nm (green) . • The phosphors demonstrated excellent thermal stability. Compared with room temperature, the emission intensities of 478 nm and 530 nm of Rb 2 KNa(Li 3 SiO 4) 4 : 0.08Eu2+ phosphor at 150 °C maintained 84.48 % and 83.71 % , respectively. • Rb 2 KNa(Li 3 SiO 4) 4 : Eu2+ proves to be a promising narrow-band cyan-green phosphor with excellent luminescent performance, making it suitable for application in w-LED . [ABSTRACT FROM AUTHOR]