Luminescence characteristics of the Ce³⁺-doped garnets: The case of Gd-admixed Y₃Al₅O₁₂ transparent ceramics

The Ce-doped (Gd, Y)₃Al₅O₁₂ transparent ceramics with Gd³⁺ content of 0 to 80 mol% were fabricated using a solid-state sintering method under vacuum. Their phase compositions and structure parameters were checked by X-ray diffraction (XRD). Optical and luminescence characteristics were investigated and thoroughly discussed by transmittance, absorption spectra and luminescence examination. The Gd³⁺ ions were found of great importance to the band structure of crystal and energy state of Ce³⁺ in the garnet ceramics. Balanced Gd³⁺ admixture into the YAG lattice provided excellent color coordinates and CRI for the phosphor for warm white light illumination. This study provides an efficient approach to tailor the luminescence of the garnet phosphors.