Investigation of the rigid structure, luminescence properties of stable CaY2Al4SiO12: Bi/Tb/Sm phosphors toward wLEDs application

As energy consumption intensifies, energy saving and environmentally friendly phosphor-converted white light-emitting diodes (pc- w LEDs) have become the current research hotspots. The garnet-based CaY 2 Al 4 SiO 12 (CYAS) phosphors, with their abundant lattice sites and stable physical properties, are ideal candidates as phosphor hosts. Through comprehensive experimental and theoretical analyses, including XRD/Rietveld refinement and density functional theory (DFT) calculations, it was determined that Bi 3+ /Tb 3+ /Sm 3+ ions preferentially occupy the Y 3+ lattice site. The luminescence properties and thermal stability of CYAS: Bi 3+ /Tb 3+ /Sm 3+ have been extensively investigated. The quantum yield (QY) has been enhanced to 48.3 % due to energy transfer (ET), which is not a significant difference compared to existing phosphors, and by superposition of blue (Bi, 3 P 1 → 1 S 0 ), green (Tb, 5 D 4 → 7 F 5 ), and red (Sm, 4 G 5/2  →  6 H 5/2 ) emission, resulting in tunable spectrum and high-quality, full-spectrum white light emission. Finally, the w LED device with high color rendering index (CRI, 87), high luminous efficiency (LE, 74 lm·W −1 ), and low correlated color temperature (CCT, 4747.56 K) were fabricated by a remote ‘encapsulation’ packaging strategy, suggesting that the phosphor can be applied to high quality white light illumination.