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 nGyair 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.

Enhancing Initial Surface Adsorption for Doped Lead‐Free Copper(I) Halide Microcrystals Through a Moderate Lewis Base Ligand

“…With the increasing amount of MSA, the PLQY values exhibit an increase first and then a decrease, with the highest value at 59.3% for Cs 3 Cu 2 I 5 ‐Mn‐4 MCs ( Figure a), which may be attributed to a possible trade‐off between the blue emission of Cs 3 Cu 2 I 5 and the yellow emission of Mn 2+ . Compared with the previously reported Mn 2+ ‐doped Cs 3 Cu 2 I 5 MC or NCs, [ 23,26,29,38,49 ] the as‐prepared sample shows a higher PLQY than most of them (Table S2, Supporting Information). More importantly, this one‐pot solution method reported by us requires a shorter reaction time, lower temperature, as well as common atmospheric conditions.…”

“…The peaks at 642.2 and 651.9 eV in Mn 2p spectra of the Cu 3 Cu 2 I 5 ‐Mn‐4 sample are designated as 2p 3/2 and 2p 1/2 electronic states of Mn 2+ (Figure 1c), confirming the existence of Mn 2+ . [ 38 ] The XPS peaks of Cu 2p shift toward lower binding energies after doping of Mn 2+ (Figure S9, Supporting Information). The Cs 3d and I 3d spectra have no obvious variations (Figure S10–S11, Supporting Information).…”

Sb-enhanced Cs3Cu2I5 scintillators for ionizing radiation detection

“…In particular, the indirect ionizing radiation detection method based on scintillation refers to the use of scintillators to indirectly convert X-ray energy into visible light, which decouples the absorption and charge generation processes. 16 An ideal scintillator should have the following properties: 17,18 (1) high absorption capacity of ionizing radiation; (2) excellent radiation luminescence intensity; (3) stable and do not contain toxic elements; (4) low loss of flickering light and high collection efficiency. Commercial scintillators are normally composed of inorganic solid single crystals such as CsI:Tl + , 19 (Lu,Y) 2 SiO 5 (LYSO), 20 Bi 4 Ge 3 O 12 (BGO) 21 and GOS:Tb.…”

“…Exploring ternary copper halide perovskite scintillators with high light yields, short decay times, and tunable emission wavelengths will continue to be a promising direction of research for a considerable period. Doping is a commonly used strategy to improve material properties, 17,33 which can reduce the local symmetry of crystals, improve the self-trapped state of crystals, and enhance exciton luminescence efficiency. 29,34–36 It has been proven that antimony (Sb) doping has a positive effect on the luminescence properties of lead halide perovskites.…”

“…Thirdly, the dimensionality of Cs 3 Cu 2 I 5 properties can be effectively controlled through cation incorporation with organometallic Sb compound. Doping is a commonly used strategy to improve material properties, 17,33 which can reduce the local symmetry of crystals, improve the self-trapped state of crystals, and enhance exciton luminescence efficiency. 29,34–36,38 In this work, organometallic Sb was introduced to enhance the compatibility of inorganic perovskite with polymer matrix and modulate the dimension of metal halide perovskite, and the effect of Sb on the scintillation properties of Cs 3 Cu 2 X 5 was fully investigated.…”