High‐Resolution X‐Ray Imaging of Mn Enhanced Lead‐Free Halide Scintillators in Pixelated Array Structures

Abstract X‐ray photography plays an important role in the fields of medical treatment, security inspection, and non‐destructive testing. The high image quality depends on X‐ray detectors with excellent properties. To meet the future demand for high‐performance scintillation screens, adding a new luminescent center in Cs₃Cu₂I₅ by doping is considered. The successful incorporation of Mn brought a new luminescence peak at 565 nm. Different excitation modalities such as ultraviolet and X‐rays have the ability to tune luminescence. X‐ray can promote the energy transfer efficiency of self‐trapped excitons and non‐radiative intermediate trap states to doping Mn²⁺ ions. This results in a higher radioluminescence intensity of a radioluminescence light yield of 65 000 Photons MeV⁻¹. Subsequently, a Cs₃Cu₂I₅: Mn scintillation screen is prepared by anodized aluminum oxide (AAO) template. The array channel structure of the AAO template strongly suppresses the internal scintillation light scattering, allowing more scintillation photons to be emitted efficiently. Under the combined effect of Mn‐enhanced radioluminescence properties and AAO template suppressed light scattering, it obtains the lowest detection limit of 49 nGy_air s⁻¹. High X‐ray imaging quality has been achieved for circuit boards, beetles, and ball‐point pens and reached a high X‐ray imaging resolution of 11.8 lp mm⁻¹.