Multicolor regulation of trivalent lanthanide ions-codoped boggildite-type phosphor toward superb warm white luminescence for white light-emitting diodes

Mineral-inspired single-component phosphors with multicolor-emitting feature are desirable for illumination-grade solid-state lighting applications. However, it remains challenging in phosphors to directly achieve the warm white-light modulation via the intrinsic f–f transitions from trivalent lanthanide cations. Herein, substantially regulatable multicolor luminescence is realized in the single-component boggildite-type (Na2Sr2Al2(PO4)F9) phosphors. The warm white-emitting phosphor Na2Sr2Al2(PO4)F9:0.07 Tb3+, 0.05Eu3+ was firstly obtained, and it possesses multiple emission bands distributing in the entire visible spectral region and exhibits desirable thermal stability (86.2%@423 K of the integrated fluorescence intensity at 298 K) and high internal quantum efficiency (83.8%), overwhelming other currently representative single-component white-emitting phosphors. Multicolor emission evolution in large color gamut covering the warm white region was reached via fine regulating Tb3+/Eu3+ dopant ratio in Na2Sr2Al2(PO4)F9:0.07 Tb3+, zEu3+ (z = 0–0.10) phosphors contingent on their energy transfer between Tb3+ and Eu3+, theoretically verified by the Kushida–Malta model. A fabricated white light-emitting diode prototype coated with the composition-optimized Na2Sr2Al2(PO4)F9:0.07 Tb3+, 0.05Eu3+ phosphor finally provided ideal warm white light output with color rendering index and correlated color temperature of 88.7 and 3384 K, as well as favorable luminous efficacy of 62.4 lm/W, demonstrating its significant potential for industrial applications in illumination-grade warm white light-emitting diode devices. Guided by the known mineral-type structural prototypes, the present study demonstrates a unique approach to realizing the unexpected warm white emission in novel mineral-type phosphor system by only doping trivalent lanthanide ions to achieve the excellent luminescence performance for solid-state lighting applications.