Study On The Properties Of Thermoluminescence Of The Rare Earth Element Doped Calcium Fluoride Nanomaterials

With the continuous development of nuclear energy and related fields,all kinds of radiation come into people’s vision.It has become a must to monitor all kinds of radiation,dosimeter became an indispensable tool.At the same time,it has been found that nanomaterials have a very good performance with the development of nanomaterials.So in this paper,the thermoluminescence properties of rare earth doped CaF₂ nanomaterials irradiated by gamma ray have been studied.The glow curve of synthesized nanomaterials have been analyzed by the Tm-Tstop method combined with CGCD（Computerized Glow Curves De-convelved）software.First of all,gadolinium doped calcium fluoride（Ca F2:Gd）nanoparticles were produced by using the hydrothermal method.X-ray diffraction（XRD）,scanning electron microscope（SEM）and energy dispersive spectrometer（EDS）patterns were utilized to characterize the nanomaterials.The particle size of about 44 nm was evaluated from XRD data,crystal present cubic crystal system structure.Nanomaterial composition elements are Ca,F,Gd.The optimized concentration of Gd impurity was found at 0.6 mol%.The sensitivity of two kinds of materials are almost the same to compare the glow curve of the nanomaterials and sintering materials.The glow peak of sintering materials are 102 oC and 172 oC,the glow peak of nanomaterials are 133 oC and 288 oC.Also the thermoluminescence properties of CaF₂:Gd nanomaterials irradiated by gamma ray have been studied.It was found that the nanomaterial has a good linear dose from 1Gy to 10000 Gy for the gamma ray with good decay and repeatability.Secondly,erbium doped calcium fluoride（CaF₂:Er）nanoparticles were produced by using the hydrothermal method.X-ray diffraction,scanning electron microscope and energy dispersive spectrometer patterns were utilized to characterize the nanomaterials.The particle size of about 45 nm was evaluated from XRD data,crystal present cubic crystal system structure.The optimized concentration of Er impurity was found at 1.8 mol%.The sensitivity of nanomaterials is 5 times and 3 times of sintering materials and LiF:Mg,Ti（JR1152A）commercial dosimeter to compare the glow curve of the nanomaterials,sintering materials and LiF:Mg,Ti（JR1152A）commercial dosimeter.The glow peak of nanomaterials is about 83 oC,the glow peak of sintering materials are about 125 oC and 195 oC.Also the thermoluminescence properties of CaF₂:Er nanomaterials irradiated by gamma ray have been studied.It was found that the nanomaterial has a good linear dose from 1Gy to 1000 Gy for the gamma ray with good repeatability.In a month of decay measurement,decay of nanomaterials is about 13%。Finally,the glow curve of synthesized CaF₂:Gd and CaF₂:Er nanomaterials have been analyzed by the Tm-Tstop method combined with CGCD software.The overlapping peak of CaF₂:Gd nanomaterials are 399.15,421.15,447.15 and 559.15 K,the value of FOM is 2.167%.The overlapping peak of CaF₂:Er nanomaterials are 350.15,370.15,390.15,406.15,426.15,468.15 and 508.15 K,the value of FOM is 1.149%.At the same time also the kinetic parameters of glow peaks are obtained.