Eu³⁺‐Doped Phosphor‐in‐Glass: A Route toward Tunable Multicolor Materials for Near‐UV High‐Power Warm‐White LEDs

A novel route toward tunable multicolor materials through phosphor‐in‐glass (PiG) technology is proposed in this work. Before that, an ultrastable Eu³⁺‐doped precursor luminescent glass frit without thermal quenching in the temperature range of 80–480 K is developed to serve as an encapsulant that not only protects the embedded phosphor but also provides the red‐emitting component for the PiG. By adjusting the mass ratio of Sr₄Al₁₄O₂₅:Eu²⁺ phosphor to glass frit, a series of tunable multicolor Eu³⁺‐doped PiG is obtained and exhibits a good resistance to the harsh conditions. Meanwhile, the luminescent color of Eu³⁺‐doped PiG can be modified by changing the excitation wavelength or ambient temperature. Finally, corresponding Eu³⁺‐doped PiG encapsulated high‐power light‐emitting diodes are further fabricated, especially the warm white‐light‐emitting diodes (WLEDs), showing good color stability under different drive currents and with different periods of operating time. All these results indicate that Eu³⁺‐doped PiG is a potential color converter applied in the high‐power warm‐WLEDs and the route above opens up a facile and potential approach to obtain multicolor materials.