Airflow-Controlled Crystallization for a Multi-Inch 2D Halide Perovskite Single-Crystal Scintillator for Fast High-Resolution X-ray Imaging

Abstract

Theoretical analyses indicate that a two-dimensional (2D) layered metal halide perovskite, with its unique quantum-well structure and large exciton binding energy, should render both fast and strong fluorescence, making it ideal for fast X-ray imaging. Herein, an airflow-controlled solvent evaporation system is designed to grow an inch-sized 2D (PEA) 2 PbBr 4 single crystal (SC) at low temperature (30 °C). Under X-rays, the (PEA) 2 PbBr 4 SC exhibits a high light yield of 73226 photons/MeV and a fast response time of 14 ns, which is approximately 1.4 times higher and 75 times faster than those of the commercial CsI:Tl scintillator (54000 photons/MeV and 1049 ns), respectively. With such significant merits, an X-ray imager is assembled by integrating a (PEA) 2 PbBr 4 SC with dimensions of 57 × 41 mm 2 for X-ray imaging, and a high spatial resolution of 11.1 lp/mm is achieved, which demonstrates the application prospect of the large-size (PEA) 2 PbBr 4 SC in high-speed nondestructive medical diagnosis.

Transparent Organic and Metal Halide Tandem Scintillators for High-Resolution Dual-Energy X-ray Imaging

“…Benefiting from low interlayer light crosstalk associated with high transparency of the top and bottom scintillator, the spatial resolution of the TFB sandwich structure scintillator still exhibits about 18 lp/mm (Figure b, iii and iv and Figure S9). To conclude here, the TFB sandwich structure scintillator boasts an impressively high spatial resolution, which is comparable to and in some cases even surpasses the results of advanced single-layer scintillators made from organic and metal halide materials. ,,− Being in this regime, a comparison of the spatial resolution of this work with other reported scintillators for X-ray imaging was summarized in Figure S10. As a further control experiment, commercial CsI:Tl and LYSO:Ce scintillators with the equivalent sensitive thicknesses as the TFB sandwich structure scintillator were also performed for X-ray imaging resolution measurements.…”

High-Efficiency X-ray Sensing with Recyclable Perovskite–Graphene Heterostructured Transistors

“…Futhermore, innovative nano structures have been investigated as scintillators with fine spatial resolution demonstrated. 13,14 Additionally, 2D perovskites have been studied and exhibited high light yields over 10 4 photon/MeV 15,16 In comparison, the direct conversion mechanism employs materials such as perovskites as semiconductors that directly convert ionizing photons to measurable signals, have high spatial resolution due to no problematic light spread issues seen in indirect conversion sensors, and do not require additional readout electronics like diodes or PMTs. Furthermore, if direct conversion sensors can utilize an ultrahigh quantum efficiency, via a gain mechanism at low bias, then this holds great promise for low photon flux detection applications.…”

“…While traditional indirect sensors used in medical imaging, such as CsI­(Tl), have undesireable spatial resolution for mammography applications due to light spread down the “needle-like” columnar structures, CsPbBr 3 quantum dots have recently been integrated to scintillator screens for high-resolution imaging applications. Futhermore, innovative nano structures have been investigated as scintillators with fine spatial resolution demonstrated. , Additionally, 2D perovskites have been studied and exhibited high light yields over 10 4 photon/MeV , …”

Cs3Cu2I5 Nanocrystals with Near-Unity Photoluminescence Quantum Yield for Stable and High-Spatial-Resolution X-ray Imaging

“…Liu’s group designed an airflow-controlled solvent evaporation system to grow an inch-sized 2D (PEA) 2 PbBr 4 single crystal. The (PEA) 2 PbBr 4 SC exhibits a high light yield of 73,226 photons/MeV and a fast response time of 14 ns . However, their environmental stability and operational stability under X-ray illumination still need to be improved …”

“…The (PEA) 2 PbBr 4 SC exhibits a high light yield of 73,226 photons/MeV and a fast response time of 14 ns. 23 operational stability under X-ray illumination still need to be improved. 22 As the presence of Pb poses a serious threat to human health and the environment, 18,19 there have been tremendous efforts to replace Pb in the scintillator materials using copper, 24−26 manganese, 27,28 and antimony.…”