X-ray Detection Research Of Eu^2+/3+ Ion Doped Glass-ceramic Scintillato

X-rays are widely used in materials research,safety inspection,medical diagnosis,industrial nondestructive testing and space exploration.Scintillator serves as the core of indirect X-ray detection,which can convert high-energy X-rays into low-energy visible light.Inorganic single crystal scintillator（such as CsI:Tl,Bi4Ge3O12（BGO）,etc.）has excellent scintillation performance and stability.However,these single-crystal scintillators suffer from the following problems:time-consuming and expensive synthesis steps and poor device machinability.In recent years,perovskite materials have excellent scintillation properties.Unfortunately,due to phase separation and degradation are easy to occur,making it challenging in practical application.Eu²⁺/3+ions with unique structure exist in both f-f and d-f transition forms,which are widely used in X-ray detection field.Their doping in fluoride,oxide and fluorine oxide nanocrystals has excellent scintillation performance.However,it is difficult for Eu ions to exist in bivalent form in nature,and the difficulty of efficient reduction of Eu3+ ion is also the main factor for its development.In addition,the poor weather resistance of the organic packaging carrier encapsulating nanocrystals limits the detection application of scintillator materials under harsh conditions.The simple preparation,low cost,high transparency and high physical and chemical properties of glass ceramic（GC）have attracted wide attention.Therefore,the scintillation properties of Eu²⁺/3+ions doped in fluoride and oxide GC were studied in this paper,and the scintillation of GC prepared was used for X-ray detection under harsh conditions.The main research contents are as follows:1.Eu²⁺ ions were successfully reduced in silicate aluminum glass by using nano carbon powder as reducing agent and full mixing and sintering of microcrystalline glass raw materials.Eu3+ was efficiently reduced to Eu²⁺ by multiple characterization Nanocrystals of the appropriate size can be obtained by using the appropriate annealing temperature.In addition,the in situ crystallization process guarantees the high transparency and luminous uniformity of GC.2.The scintillation properties of CaF₂ GC doped with Eu²⁺ ions were investigated.The prepared material has a decay time of 972 ns,a 98%X-ray cutoff at 1.4 mm and a transparency of 84.2%.The Radioluminescence（RL）intensity of Eu²⁺is twice that of commercial BGO single crystal scintillators due to the high efficiency of blue light emission from the 5d-4f transition of Eu²⁺ ion.The minimum detectable dose rate of X-ray detection was 5 μSv/h,which was lower than the dose requirement of typical physical examination.The prepared scintillator can maintain high optical efficiency and stability even under harsh conditions due to the stable nanocrystalline structure inside and the protection of glass matrix outside,and is suitable for X-ray highresolution imaging under harsh conditions.3.Scintillation properties of Eu³⁺ doped Zn₂SiO₄ glass ceramic were investigated.The RL emission spectrum consists of a white luminescence coupled by the blue-green emission of Zn2SiO4 and the red emission of Eu3+ion 4f-4f transition,with an intensity up to 60 percent of that of commercial BGO single crystals.The X-ray absorption capacity is also stronger than that of commercial single crystal Si and Ge based semiconductor.The optical fiber with high transparency can be used for X-ray detection based on fluorescence intensity ratio.The Zn2SiO4:Eu3+ glass-ceramics annealed at 850℃ have deep traps,and the device designed for delay detection can control the removal and writing of charge carriers to complete the delayed repeated detection of X rays.It provides a reference for self-calibrated Xray detection under unknown harsh conditions.