Abstract

Abstract Lanthanide‐doped fluoride nanoscintillators (NSs) have emerged as promising candidates for X‐ray imaging. However, strong afterglow, long lifetime, and poor irradiation stability pose key challenges for real‐time dynamic X‐ray imaging. In this study, the sub‐10 nm Lu 6 O 5 F 8 :Tb NSs with tunable morphologies are prepared via incorporating Li + /Na + ions. The X‐ray excited optical luminescence (XEOL) intensity of the Lu6O5F8:15Tb/10Li NSs is stronger than that of NaLuF 4 :15 Tb NSs with a similar particle size while its afterglow is only ≈2.7% compared to that of NaLuF 4 :15 Tb NSs. Utilizing the Lu 6 O 5 F 8 :15 Tb/10Li NSs‐integrated film as a scintillator screen, a high resolution of ≈21.6 lp/mm is achieved. Even at a low dose of 0.23 µGy, the fringe detail in the electron device is clearly observed in the X‐ray image. The afterglow intensity of the Lu 6 O 5 F 8 :10Eu/10Li NSs decays to 0.7% at 40 µs, which is better than that of CsI:Tl (3.6%@40 µs). Moreover, the Lu 6 O 5 F 8 :10Eu/10Li NSs with a lifetime of 1.65 µs are verified for use in dynamic 3D X‐ray imaging. These findings represent a significant advancement in the development of new NSs for high‐performance dynamic X‐ray imaging.