Mn-Si Co-doping strategy for high-CRI and thermally stable Ce: YLuAG phosphor ceramics for laser-driven white light sources

The low color rendering index (CRI) of single-structured Ce: YAG phosphor ceramics (PCs) greatly limits their practical application in white laser-driven (LD) lighting due to the deficient red component. Traditional methods to enhance CRI often come at the expense of thermal stability, posing a challenge for widespread adoption. To address this issue, we proposed a multi-component co-doping strategy by incorporating Lu³⁺ and Mn²⁺/Si⁴⁺ into Ce: YAG PCs. Lu³⁺ incorporation stabilized the crystal lattice, maintained the spatial separation between Ce³⁺ and Mn²⁺, and reduced Ce³⁺-Mn²⁺ energy transfer, thereby suppressing nonradiative transitions and ensuring excellent thermal stability. Additionally, Mn²⁺-Si⁴⁺ co-doping achieved high-concentration incorporation through charge compensation, effectively sustaining strong red emission to enhance the CRI. The optimized Mn10 sample demonstrated exceptional thermal stability, retaining 83.2 % of its emission intensity at 423 K. Moreover, the CRI of Ce,Mn-Si:YLuAG increased from 57.5 to 84.5, a 47 % improvement compared with Ce:YLuAG under high-power LED excitation. These results indicated that Ce, Mn-Si: YLuAG PC, with its excellent CRI and thermal stability, is a highly promising color converter for highpower white LEDs and LDs. Keywords: Ce: YAG phosphor ceramic; Ce³⁺-Mn²⁺ codoping; white LDs; color rendering index; crystal-field splitting.