Near-unity broadband luminescent cuprous halide nanoclusters as highly efficient X-ray scintillators

• Published in: Science China materials Vol. 66; no. 12; pp. 4764 - 4772
• Main Authors: Li, Dong-Yang, Tan, Qingwen, Ren, Meng-Ping, Wang, Wen-Qi, Zhang, Bing-Lin, Niu, Guangda, Gong, Zhongliang, Lei, Xiao-Wu
• Format: Journal Article
• Language: English
• Published: Beijing Science China Press 01.12.2023; Springer Nature B.V
• Subjects: Afterglows; Broadband; Chemistry and Materials Science; Chemistry/Food Science; Excitons; Halides; Lead free; Light emission; Materials Science; Nanoclusters; Nuclear radiation; Perovskites; Photoluminescence; Radiation; Scintillation counters; Spatial resolution; Unity; X ray imagery; X-ray radiography; radioluminescence; zero-dimension hybrid cuprous halides; photo-luminescence; X-ray imaging
• ISSN: 2095-8226; 2199-4501
• DOI: 10.1007/s40843-023-2649-1

X-ray scintillators as functional energy materials possess the powerful ability to convert high-energy radiation into visible light with wide applications in various nuclear radiation fields. In this regard, three-dimensional (3D) lead perovskite nanocrystal-based X-ray scintillators have attracted extensive attention, but their low light yield and serious toxicity extremely restrict their further applications. To address these issues, a family of 0D hybrid cuprous halides of A 2 Cu 4 X 6 (A = PTPP, TPA; X = Br, I) based on discrete [Cu 4 X 6 ] 2− nanoclusters were demonstrated as highly desirable lead-free scintillators. Upon excitation of both ultraviolet and blue light, these halide nanoclusters displayed that self-trapped excitons induced broadband light emissions from green to red with near-unity photoluminescent quantum yield (PLQY, 93.1%) andlarge Stokes shifts (>1.3 eV). Significantly, the high PLQY, negligible self-absorption, and strong X-ray attenuation from [Cu 4 X 6 ] 2− nanoclusters endowed them with extraordinary radioluminescence properties. The linear radioluminescence intensity response to a wide range of X-ray dose rates gave an acceptable detection limit of 0.7563 µGy air s −1 , which was lower than the required value for regular medical diagnostics (5.5 µGy air s −1 ). X-ray imaging demonstrated an ultrahigh spatial resolution of 14.83 lp mm −1 and negligible afterglow (1.3 ms), showcasing potential applications in X-ray radiography. Overall, the combined superiorities of nontoxicity, high light yield, excellent stability, and good radiation hardness make cuprous halide nanoclusters excellent scintillators.