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 (Ra = 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.