Highly Resolved X‐Ray Imaging Enabled by In(I) Doped Perovskite‐Like Cs₃Cu₂I₅ Single Crystal Scintillator

Abstract

Low‐dimensional perovskite halides have shown a great potential as X‐ray detection materials because of efficient exciton emissions originating from strongly spatially localized charge carriers. Nonetheless, most of them have a scintillation yield far below their theoretical limits. Here, it is found that the harvesting efficiency of produced charge carriers can be significantly enhanced via a small amount of In+ doping in these highly localized structures. A bright and sensitive zero‐dimensional Cs3Cu2I5:In+ halide with efficient and tunable dual emission is reported. The radioluminescence emission of Cs3Cu2I5:In+ crystals under X‐ray excitation consists of a self‐trapped exciton emission at 460 nm and an In+‐related emission at 620 nm at room temperature. In+ doping enhances the photoluminescence quantum efficiency (PLQY) of Cs3Cu2I5 from 68.1% to 88.4%. Benefiting from the higher PLQY, Cs3Cu2I5:In+ can achieve an excellent X‐ray detection limit of 96.2 nGyair s−1, and a superior scintillation yield of 53 000 photons per MeV, which is comparable to commercial CsI:Tl single crystals. As a result, a remarkable X‐ray imaging resolution of 18 line pairs mm–1 is demonstrated, which is so far a record resolution for single crystal perovskite‐based flat‐panel detectors. These results highlight the importance of efficient harvesting of carriers (and excitons) in low‐dimensional perovskites for radiation detection applications.

Self-surfactant room-temperature synthesis of morphology-controlled K0.3Bi0.7F2.4 nanoscintillators

“…5a. By combining a commercial digital camera and a 50 keV X-ray source, 49,58,59 the X-ray imager prototype can reveal the detailed structural information of imaging objects by using KBF:10% Ln scintillator film. Based on the optimized composition, a wafer of KBF:10% Ln-PDMS scintillator film with a 2 cm diameter was prepared, which shows a white color under ambient light, as shown in Fig.…”

“…S14, ESI†), demonstrating their great promise for high-contrast X-ray imaging. Compared with the prevailing perovskite scintillators such as Cs 2 Ag 0.6 Na 0.4 In 0.85 Bi 0.15 Cl 6 , 49 Cs 3 Cu 2 I 5 :In + , 59 and CsPbX 3 , 60 the newly developed KBF:10% Ln nanoscintillators provide a number of merits such as nontoxic compositions, simple and rapid synthetic route, and excellent photostability and radioluminescence performance, which will lay the foundation to develop new categories of inorganic scintillators for promising application in low-dose radiography.…”

Halide Perovskite: A Promising Candidate for Next‐Generation X‐Ray Detectors

“…In addition, the PLQY of In + ‐doped Cs 3 Cu 2 I 5 also increased from 68.1 to 88.4%. [ 181 ] Because of the higher PLQY, Cs 3 Cu 2 I 5 :In + achieved an X‐ray detection limit as low as 96.2 nGy air s −1 . Furthermore, its scintillation yield of 53 000 photons MeV −1 is comparable to commercial single‐crystal CsI:Tl.…”

A-site FA+engineering boosting photoluminescence efficiency and stability of cesium copper iodine (Cs3Cu2I5) perovskites

“…13 Furthermore, Cs 3 Cu 2 X 5 (X = Cl, Br, I) perovskites have broad-spectrum emission and large Stokes shifts, which make them very suitable in light-emitting applications 11,14–17 and scintillators. 18,19…”