Highly Luminescent Zero-Dimensional Organic Copper Halides for X-ray Scintillation

Abstract

The present work reports highly efficient flexible and reabsorption-free scintillators based on two zero-dimensional (0D) organic copper halides (TBA)­CuX2 (TBA = tetrabutylammonium cation; X = Cl, Br). The (TBA)­CuX2 exhibit highly luminescent green and sky-blue emissions peaked at 510 and 498 nm, with large Stokes shifts of 224 and 209 nm and high photoluminescence quantum yields (PLQYs) of 92.8% and 80.5% at room temperature for (TBA)­CuCl2 and (TBA)­CuBr2 single crystals (SCs), respectively. Interestingly, above room temperature, their PLQYs increase with temperature and reach near unity at 320 and 345 K for (TBA)­CuCl2 and (TBA)­CuBr2, respectively. The excellent properties originate from self-trapped excitons (STEs) in individual [CuX2]− quantum rods, which is demonstrated by the temperature-dependent PL, ultrafast transient absorption (TA) combined with density functional theory (DFT) calculations. The (TBA)­CuX2 scintillators show bright radioluminescence (RL), impressive linear response to dose rate in a broad range, and high light yields. Their potential application in X-ray imaging is demonstrated by using (TBA)­CuX2 composite scintillation screens. Importantly, flexible scintillators are demonstrated to be superior than flat ones for imaging nonplanar objects by conformally coating, which produce accurate images with negligible distortion.

Photophysics in Zero‐Dimensional Potassium‐Doped Cesium Copper Chloride Cs3Cu2Cl5 Nanosheets and Its Application for High‐Performance Flexible X‐Ray Detection

“…Based on this, its flexible imaging was further explored. When a metallic spring was placed in a curved manner and the X-ray images recorded with the projection and attached mode in Figure 5c, [51] an apparent distortion with the blurred imaging at both ends of the spring using the flat scintillator can be seen. On the contrary, when the film conformally attached on the cup, the entire spring can be clearly imaged, exhibiting the key advantage of flexible scintillators.…”

Cesium Lead Halide Nanocrystals based Flexible X‐Ray Imaging Screen and Visible Dose Rate Indication on Paper Substrate

“…Another important question for X‐ray detection should be kept in mind is that the DNA of human beings will be damaged when exposed to high cumulative dose irradiation, [ 5,7 ] so detecting the dose rate of X‐ray with high accuracy and convenient operation is also aspired. However, commonly used personal radiation dose tablet cannot display the real‐time dose rate (DR), while radiation detectors are expensive and can hardly be carried around.…”

Template Assembled Large‐Size CsPbBr3 Nanocomposite Films toward Flexible, Stable, and High‐Performance X‐Ray Scintillators

“…[6] Thus, it is of great importance to explore efficient luminescent materials with a high energy-converting efficiency and an excellent stability for scintillators. Among the reported emitters, inorganic perovskites DOI: 10.1002/lpor.202100736 gain great researching interests in the fields such as solid-state lighting [7][8][9] and radiation detection, [10][11][12] due to the facile preparation method, [13][14][15] high absorption coefficient, [16][17][18][19] high defect tolerance, [20][21][22][23][24] and tunable emission. [25][26][27][28] However, their commercialization still suffers from a formidable issue of instability of perovskites, in which the phase separation and degradation occur when exposed to water and oxygen for long time.…”