Traps-engineering in LiGa5O8:xTb3+by Li/Ga ratios for X-ray multimode imaging

X-ray scintillators are crucial for medical, industrial, and security imaging systems. However, achieving dual-mode of real-time and delayed imaging within a single matrix still faces challenges. Herein, LiGa 5 O 8 : Tb 3+ was successfully synthesized by the high-temperature solid-phase method. By controlling the atmosphere and optimizing the Li + /Ga 3+ ratio, the trap structure of LiGa 5 O 8 : Tb 3+ spinel phosphors is effectively adjusted, which achieved excellent dual-mode imaging. The air-synthesized Li 1.6 Ga 5 O 8 :4 %Tb 3+ exhibits intense X-ray excited persistent luminescence (X-PersL, 595 nm), while the sample of LiGa 5 O 8 :Tb 3+ reduced in H 2 /N 2 shows enhanced radioluminescence (RL) without X-PersL. This precise manipulation of anti-occupancy defects controls the charge trapping/detrapping dynamics, enabling switchable RL (real-time imaging) and X-PersL (delayed imaging) modes through the single Tb 3+ ions emission. The result resolves the incompatibility between prompt and persistent X-ray responses in conventional scintillators. The defect-regulation method establishes a universal strategy for developing scintillators compatible with complex operational demands, advancing high-performance X-ray imaging technologies.