【作者】 黄杰；

【导师】 徐强；

【作者基本信息】 南京航空航天大学 ， 工程硕士（专业学位）， 2022， 硕士

【摘要】 近些年来钙钛矿由于其优异的光电性能如大吸收本领、可调带隙、快衰减时间、低制备成本,已经成为光伏以及光电探测领域的新星材料,因此有望成为闪烁体应用于核探测领域。为了克服传统液体闪烁体发光效率不高、有效原子质量较少等不足,本论文通过将其与钙钛矿材料相结合,在此基础上详细地研究了该钙钛矿量子点液体闪烁体的闪烁特性,为后续应用于X射线探测领域打好基础。本论文取得的研究进展如下:1.基于改良的辅助配体再沉淀法引入了短链烷基胺并选择了最优比例,得到了高结晶质量、高透射率、光学性能优异的钙钛矿量子点液闪,并利用XRD、HRTEM、PL、透射谱等分析方法对其进行了初步表征,为后续进行X射线探测性能研究提供材料支撑。2.进行了对钙钛矿量子点液闪材料闪烁性能的测试,发现影响其光学性能的具体反应条件及规律。通过改变两种钙钛矿液闪中卤素原子的含量,实现了PL发光在紫外-可见光范围内的连续可调。对样品进行不同剂量下X射线激发光谱的测量,得到了相对光输出与X射线剂量率的函数,结果显示钙钛矿量子点液闪的相对光输出在0.3到520μGys^-1的宽范围内与X射线剂量率成正比,并获得了37.14和23.87 n Gys^-1的探测剂量率限值。研究了辐照、温度对于钙钛矿量子点液闪光学性能的影响:当总剂量达到2.08 k Gy时,MAPb Br₃和Cs Pb Br₃液闪的PL相对光输出分别下降到原来的53.8%与62.6%。两者在95℃下的XEL相对光输出分别保持在室温下的80%和40%左右。此外,两种样品在3ps脉冲X射线下具有40-60ns的快衰减时间。3.合成了PBD/POPOP/MAPb Br₃量子点液闪,通过表征发现产生了有效的荧光共振能量转移过程。与单独MAPb Br₃量子点液闪相比,PBD/POPOP/MAPb Br₃量子点液闪材料在X射线下的闪烁性能有明显提升,最佳浓度（92mg/m L）的PBD/POPOP/MAPb Br₃量子点液闪的闪烁发光与钙钛矿液闪相比有着5.63倍的增强。更多还原

【Abstract】 In recent years,perovskite has become a new star material in the field of photovoltaic and photoelectric detection due to its excellent photoelectric properties,such as large absorption power,adjustable band gap,fast decay time,and low production cost.Therefore,it is expected to become a scintillator for nuclear detection field.In order to overcome the shortcomings of traditional liquid scintillators such as low luminous efficiency and low effective atomic mass,this thesis combines it with perovskite materials,and on this basis,a detailed study of the perovskite quantum dot liquid scintillator The scintillation characteristics lay a good foundation for subsequent applications in the field of X-ray detection.The research progress made in this paper is as follows:1.Based on the improved auxiliary ligand reprecipitation method,short-chain alkyl amines are introduced and the optimal ratio is selected,and the perovskite quantum dot liquid scintillation with high crystal quality,high transmittance and excellent optical performance is obtained,and XRD is used analytical methods such as HRTEM,PL,and transmission spectroscopy have been initially characterized,providing material support for subsequent X-ray detection performance research.2.The scintillation performance of the perovskite quantum dot liquid scintillation material was tested,and the specific reaction conditions and rules affecting its optical performance were found.By changing the content of halogen atoms in the two perovskite liquid scintillations,the continuous adjustment of PL luminescence in the ultraviolet-visible light range is realized.The X-ray excitation spectra of samples were measured at different doses,and the relative light output as a function of the X-ray dose rate was obtained.The results showed that the relative light output of the perovskite quantum dot liquid scintillation was within a wide range of 0.3 to 520μGys^-1.The X-ray dose rate is proportional,and the detection dose rate limits of 37.14 and 23.87 n Gys^-1are obtained.The effects of irradiation and temperature on the flash performance of perovskite quantum dot liquids were studied:when the total dose reached 2.08 k Gy,the relative light output of PL of MAPb Br₃and Cs Pb Br₃liquid flashes decreased to 53.8%and 62.6%,respectively.The XEL relative light output of the two at 95°C is kept at about 80%and 40%at room temperature,respectively.In addition,the two samples have a fast decay time of 40-60ns under 3ps pulsed X-ray.3.The PBD/POPOP/MAPb Br₃quantum dot liquid scintillation was synthesized,and an effective fluorescence resonance energy transfer process was found through characterization.Compared with single MAPb Br₃quantum dot liquid scintillation,the scintillation performance of PBD/POPOP/MAPb Br₃quantum dot liquid scintillation material under X-rays has been significantly improved,and the best concentration（92mg/m L）of PBD/POPOP/MAPb Br₃quantum dot liquid scintillation Compared with the perovskite liquid scintillation,the scintillation luminescence has a 5.63 times enhancement.更多还原