Amorphous Structure Engineering for Fabricating Highly Efficient Eu ²⁺ ‐Doped Red‐Emitting Luminescent Glass Ceramics

Eu 2+ ‐doped red‐emitting color converters are extremely scarce and often exhibit limited photoelectric performance and thermal stability under high‐flux solid‐state lighting (SSL) conditions, primarily due to imprecise control of Eu 2+ site occupancy and the lack of a robust protective matrix. In this work, high‐performance red‐emitting Mg 2 Al 4 Si 5 O 18 (MAS): Eu 2+ glass‐ceramics (GCs) were developed via amorphous structure engineering. This composite material demonstrates a high crystallinity of 98.2%, an internal quantum yield (IQE) of 99.8%, an external quantum yield (EQE) of 73.2%, and an integrated luminescence intensity loss of only 7.0% at 423 K, presenting competitive overall performance in state‐of‐the‐art red‐emitting color converters. Further, the broad applicability and potential of the MAS: Eu 2+ GCs in lighting applications were verified through the fabrication of high‐quality light‐emitting diodes (LEDs) excited by violet chips and blue laser‐driven lighting systems. This study provides systematic guidance for the targeted development of Eu 2+ ‐doped luminescent materials, particularly Eu 2+ ‐doped GCs, and contributes to the development of next‐generation lighting technologies.