Near-Infrared Emitting Rare-Earth Doped Perovskite Scintillator for X-Ray Flexible Imaging

High-performance X-ray scintillation detectors are crucial for X-ray imaging applications, relying on scintillators with high light-yield (LY). In contrast to conventional scintillators with large bandgaps ( E g ), halide perovskite materials with low E g exhibit high LY, emerging as next-generation scintillation materials. Additionally, doping with rare-earth ions extends the emission wavelength to the near-infrared (NIR) region, effectively suppressing light self-absorption of perovskite materials. Here, we fabricated a Ytterbium-ion (Yb 3+ ) doped CsPbCl 3 : 2%Yb 3+ single crystal (SC) with a large-size of Φ30 × 40 mm via the Bridgman method, which exhibits a low E g of 2.88 eV and efficient NIR luminescence centered at 985 nm, achieves a high steady state LY of 83 703 photons MeV −1 , and a large effective “Stokes shift” of 563 nm. Furthermore, we prepare a series of flexible scintillation films by embedding CsPbCl 3 : 2%Yb 3+ powder in polydimethylsiloxane (PDMS). Owing to the efficient NIR luminescence, these films enable clear X-ray imaging even under bright white-LED interference, demonstrating a low X-ray detection limit of 17.8 nGy air s −1 and a high spatial resolution of 10 lp mm −1 . This work provides a high-LY NIR scintillator for X-ray flexible imaging, paving the way for low dose-rate X-ray imaging for portable and fast radiography.