Application Of MOFs And MOGs In X-ray Detection And Imaging

Between ultraviolet and gamma rays in wavelength,X-rays have a considerable penetration.At various locations of substances,there are variations in the density and thickness of the tissue structure.The X-ray will create varying absorption when it enters the item.As a result,X-ray has a variety of uses in domains such as industrial inspection,security screening,and medical diagnosis.With increasing demands on X-ray imaging and detection,conventional scintillation materials are difficult to meet.Therefore,it is of great academic significance and practical value to explore new X-ray detection materials with high X-ray blocking capability,high optical efficiency,high stability,non-toxic and environmental protection.In fact,none of the X-ray detection equipment can meet these requirements at the same time.However,due to their photophysical characteristics,notable luminescent stability,brief fluorescence life,and the environmentally sound properties found in prior studies,MOFs and MOGs are anticipated to be ideal X-ray detection materials.In this article,the principle and performance requirements of X-ray detection technology are summarized,and advances in X-ray detection materials research in recent years are discussed.On that basis,we used organic ligands with AIE luminescent groups and metals with a high order number to synthesize MOFs and MOGs under solvothermal reaction conditions.The fluorescence characteristics of the two materials were examined and the X-ray scintillation characteristics of the materials were tested in experiments.In addition,MOF and MOG materials are used to prepare composite films,thereby performing high-resolution imaging of organic samples.The specific results of the study are as follows:1.Using zirconium chloride（Zr Cl₄）and tetris[4-（4’-carboxyphenyl）phenyl]ethylene（H₄ETTC）as raw materials,the high luminescence zirconium based MOF,PCN-94,was prepared under solvothermic conditions.It showed strong AIE effect under UV and X-ray irradiation.The X-ray detection limit is less than 1.6μGy s^-1.A flexible composite scintillating film with excellent imaging performance was prepared by integrating Y-PCN-94 into a polymer matrix（PDMS）.The scintillating film has a linear imaging resolution of 14.3 lp mm^-1.2.Compared with organometallic frame materials,organometallic gel materials have denser network structure.By solvothermal reaction of 1,1,2,2-tetrad（4-carboxylbenzene）ethylene（H₄TCPE）and zirconium nitrate（Zr（NO₃）₄·5H₂O）in distilled water and N,N-dimethylformamide（DMF）,a metal-organic gel material with high luminescence efficiency（YTU-1000）was prepared.With the introduction of the IEA group,YTU-1000 has an elevated quantum efficiency of 95.45%and a detection limit of 44 n Gy s^-1 for radiography.Based on the excellent chemical and physical stability of YTU-1000,we use electroplating for the preparation of nanocomposite films.Scintillation films achieve a spatial imaging resolution of 20 lp mm^-1,which is suitable for the development of large-area membranes.