The Luminescence Properties of Sm³⁺ or Tb³⁺ —doped Lu₃Ga₂Al₃O₁₂ Phosphors for X-ray Imaging

Sm³⁺ or Tb³⁺ -doped Lu₃Ga₂Al₃O₁₂ phosphors were synthesized by using a solid-state reaction method with Lutetium oxide, gallium oxide and aluminum oxide as host materials, samarium oxide and terbium oxide as doping materials. The mixed powders were sintered at 1500 °C for 5 hours by using a horizontal furnace. In this study, the structures of Sm³⁺ or Tb³⁺ -doped Lu₃Ga₂Al₃O₁₂ phosphors were observed using an XRD (X-ray diffraction). The emission spectrum of Sm³⁺ -doped Lu₃Ga₂Al₃O₁₂ phosphor shows 550–650 nm in wavelength due to ⁴G_j to ⁶H_j. The measurement of emission spectrum of Tb³⁺ -doped Lu₃Ga₂Al₃O₁₂ phosphor was confirmed to 450 to 650 nm wavelength due to ⁵D_j to ⁷F_j. These phosphors have a sharp emission spectrum due to their physical properties of f-f transition. The Lu₃Ga₂Al₃O₁₂ has a high effective Z-number (Z_eff = 57) which is sensitive to X-ray or γ-ray. Therefore Sm³⁺ or Tb³⁺ -doped Lu₃Ga₂Al₃O₁₂ phosphors can be applied for diagnostic X-ray imaging in the medical field.