Color tunable NaCaLa(MoO₄)₃: Tb³⁺, Eu³⁺ phosphors for LED and optical anti-counterfeiting

A series of NaCaLa(MoO₄)₃: Tb³⁺, Eu³⁺ phosphors was synthesized via the high-temperature solid-state method. By regulating the concentration of Eu³⁺, the luminescent color of the phosphor can be continuously modulated, starting from green, passing through yellow, and ultimately turning to red. The analysis results of the material properties reveal that the adjustable luminescent color of the phosphor originates from energy transfer between Tb³⁺ and Eu³⁺ ions, with the transfer mechanism following a dipole-dipole interaction model. Warm white light-emitting diode devices with a color rendering index (CRI) of 84.8 and a correlated color temperature (CCT) of 3244 K were fabricated using NaCaLa(MoO₄)₃: 0.2Tb³⁺, 0.04Eu³⁺, and blue phosphor BaMgAl₁₀O₁₇: Eu²⁺ as raw materials. Moreover, under excitation of different wavelengths, this phosphor exhibits different luminescent colors. This unique photoluminescent property can be applied to the design of anti-counterfeiting labels. The results show that this material exhibits promising potential for applications in warm white LED and optical anti-counterfeiting.