A Single-Phase High-Color-Rendering NaAlSiO4:Pb2+/Tb3+/Eu3+ Phosphor for White Light-Emitting Diodes

Abstract

The development of single-phase broadband white-emitting phosphors has emerged as a critical research frontier for advanced solid-state lighting technologies. Herein, the successful synthesis of NaAlSiO₄:Pb²⁺/Tb³⁺/Eu³⁺ phosphors is reported through high-temperature solid-state reactions, achieving tunable multicolor emission and full-spectrum white light via rational energy transfer (ET) engineering. The strategic co-doping scheme enables dual ET pathways—Pb²⁺→Tb³⁺ (dipole–dipole) and Pb²⁺→Eu³⁺ (dipole–dipole)—mediated by optimal energy level alignment. The optimized NaAlSiO₄:0.01%Pb²⁺/0.01%Tb³⁺/0.005%Eu³⁺ phosphor demonstrates white emission under 271 nm excitation, integrating blue (400 nm, Pb²⁺), green (487/551 nm, Tb³⁺), and red (592-704 nm, Eu³⁺) spectral components. Fabricated white LED devices exhibit superior photometric performance with a color rendering index (CRI) of 93.8 and correlated color temperature (CCT) of 4450 K, representing 30% CRI enhancement and 32% CCT reduction compared to commercial YAG:Ce³⁺. This work demonstrates the great potential of NaAlSiO₄:Pb²⁺/Tb³⁺/Eu³⁺ phosphors for use in WLED applications and paves the way for designing high-performance single-matrix phosphors through controlled multi-dopant energy transfer systems.