X-Ray Micro-CT And Scintillator Material Characterization

X-ray Micro-CT imaging technology has a wide range of applications in medical diagnosis,industrial testing,material performance analysis,etc.The demand of for Micro-CT imaging performance increases with the continuous development of technology,high speed,super resolution and multi-function become the development direction of Micro-CT.As one of the main devices of Micro-CT imaging system,detector is the key factor to determine the imaging quality.In order to meet the application requirements,large area,low-cost and flexible high-performance detector has become research hotspot.The performance of scintillation imaging is determined by the matching between the scintillation in the detector and the photoelectric sensor,so it is important and valuable to improve the performance of scintillator to increase the performance of Micro-CT imaging.In this paper,CsPbBr₃-based perovskite scintillator thin films were prepared by a new self-assembly synthesis method,which exhibited fluorescence performance on a laboratory X-ray platform.Then,two-dimensional and Micro-CT phase contrast imaging tests were performed using high quality parallel X-ray from synchrotron light source based on the CsPbBr₃-film scintillator excellent performance,and the imaging results were analyzed and discussed and data processing was performed to explore its performance as X-ray imaging detector scintillator,furtherly.The main research work are as follows:Flexible CsPbBr₃ scintillator films with uniform thickness and large area were prepared at room temperature using self-assembly method,and their surface morphology,crystal structure,decay time and other characteristics were examined.Then their sensitivity,conversion efficiency and photoluminescence spectrum were further tested from both experimental theoretical aspects based on the laboratory with an X-ray platform.Due to its high blocking ability and conversion efficiency caused by its heavy Pb and Br atoms,the results of the experiments all indicate this CsPbBr₃ scintillator film has excellent X-ray fluorescence performance and has potential as scintillator for X-ray imaging.The imaging capability of CsPbBr₃ perovskite films with excellent scintillation luminescence was tested in a synchrotron high quality parallel X-ray platform.Two-dimension imaging of the sample with high density showed good contrast and spatial resolution.In the 1080 Micro-CT imaging experiments of the sample（bamboo）with low density,the projections,slices,and 3D images present the complex structure,density differences,and various morphological features inside the sample clearly,and the quantitative analysis of the images after phase-retrieval shows that the average contrast to noise ratio increased from 36%to 45%,and the peak value reached 60%.Moreover,the spatial resolution is less than 8.5μm.In this paper,a new method of self-assembly was used to prepared large-area,high-efficiency flexible CsPbBr₃ perovskite films excellent scintillator properties of uniform thickness and without cracks,which reduces the production cost and simplifies the synthesis steps,and the synthesized scintillator materials make flexible X-ray detectors possible.In this thesis,a new method of self-assembly was used to prepare large-area,high-efficiency flexible CsPbBr₃ chalcogenide films with excellent scintillator properties of uniform thickness and no cracks,which reduces the production cost and simplifies the synthesis steps,and the synthesized scintillator materials make flexible X-ray detectors possible.The use of X-ray equipment to characterize several properties of CsPbBr₃ scintillator films reduces the need for various expensive experimental instruments and fully demonstrates the imaging capability of CsPbBr₃ scintillator films.This perovskite material with excellent X-ray fluorescence performance can replace the traditional rigid X-ray detector scintillator and be applied to the development of large area flexible detector devices with high sensitivity and conversion efficiency,which will be of great significance in the fields of medical diagnosis,material characterization,and nondestructive testing.