Novel blue-cyan emitting Mg₂YAl₃Si₂O₁₂:Eu²⁺ garnet phosphor for high-quality warm white LEDs

The exploration of efficient, energy-saving, and environmentally friendly phosphors is crucial for the advancement of solid-state white light-emitting diodes (WLED). In this work, novel Eu²⁺-doped garnet phosphors Mg₂YAl₃Si₂O₁₂:xEu²⁺ (MYAS:xEu²⁺) that crystallize in a cubic structure were successfully synthesized. Upon excitation at 365 nm, the optimized MYAS:0.03Eu²⁺ phosphor shows a broad blue-cyan emission centered at 478 nm. The phosphor exhibits excellent thermal stability, maintaining 60.5% of its room-temperature intensity at 423 K. A warm WLED device, fabricated by combining MYAS:0.03Eu²⁺ with a commercially available red-emitting phosphor under excitation from a 365 nm UV chip, exhibited superior photometric performance at a driving current of 100 mA, with a high color rendering index (R_a = 87.4) and a comfortable correlated color temperature (CCT = 3516 K). These results highlight the great potential of blue/cyan-emitting MYAS:xEu²⁺ garnet phosphors as efficient converters for high-quality lighting applications.