新型X射线余辉材料的制备及其性能研究

发布时间：2018-05-24 12:19

本文选题：稀土发光材料 + 氟化物　；参考：《河北大学》2017年硕士论文

【摘要】：近年来,新兴的生物成像技术能够实时无损动态监测被标记的细胞在活体小动物体内的活动及反应,生物成像材料主要有量子点及纳米上转换材料等。但由于激发光源对组织的穿透能力较差,该应用只能用于体表组织。X射线由于具有良好的组织穿透性,是进行体内生物成像的理想光源,但鉴于其对人体的危害性,辐射剂量不能过大,因此X射线激发下的长余辉材料是很理想的生物成像材料。本论文的研究致力于寻找合适的材料,在低剂量X射线照射下实现长时间的余辉发射。本文分别选用高温固相法、水热法和热解法合成了氟化物为基质的荧光材料,通过X射线衍射仪、扫描电子显微镜以及能谱仪对样品的结构形貌和组成进行了分析;通过光谱仪对样品的光谱性能进行了分析;利用微弱光度计对样品的余辉性能进行了分析;利用热释光计量仪对样品的陷阱位置进行了分析,其主要内容如下:(1)采用高温固相法合成了的NaYF_4:Pr~(3+)发光粉。探究了温度、原料及氟源浓度对NaYF_4物相的影响,制备出了不同Pr~(3+)浓度掺杂的α相和β相的NaYF_4。分析了α(β)-NaYF_4:xPr~(3+)的XRD图谱,对X射线发射谱、余辉衰减以及热释光曲线做了表征。在α-NaYF_4中,Pr~(3+)的最佳掺杂浓度为3%而在β-NaYF_4中最佳掺杂浓度为1%。Pr~(3+)在β-NaYF_4中的发光及余辉性能都要优于α-NaYF_4。最后通过掺入Mg2+调节Pr~(3+)的发光,掺入Mg2+有利于β-NaYF_4:1%Pr~(3+)的发光的增强及余辉的延长。(2)采用水热法合成了NaYF_4:Pr~(3+)荧光粉。探究了氟源浓度及溶液pH值对NaYF_4物相及形貌的影响。分析了NaYF_4:Pr~(3+)的XRD、SEM和EDS图谱,对X射线发射谱、余辉衰减以及热释光曲线做了表征。高的氟源浓度利于棒状颗粒的产生,pH值越高,样品颗粒越小。当pH=5且氟钇比为1:8时,NaYF_4:Pr~(3+)的发射峰及热释光峰值最强,余辉时间也取得最大值。(3)通过热解法制备了NaYF_4:Pr~(3+)荧光粉。样品为纯相的六角相NaYF_4,颗粒大小为30-40nm。采用水热法制备了KYF_4:Pr~(3+)荧光粉。分析了KYF_4:Pr~(3+)的XRD、SEM图谱,对X射线发射谱、余辉衰减以及热释光曲线做了表征。样品为纯相的KYF_4,颗粒大小为30-40nm。在X射线的激发下,样品有有效的发光和余辉。
[Abstract]:In recent years, new biological imaging techniques can dynamically monitor the activities and responses of labeled cells in vivo, including quantum dots and nanoscale up-conversion materials. However, because of the poor penetration ability of the excitation light source to the tissue, the application can only be used in the surface tissue. Because of its good tissue penetration, it is an ideal light source for biological imaging in vivo, but in view of its harm to the human body, The radiation dose should not be too large, so the long afterglow material excited by X-ray is an ideal biomaterial. In this paper, the aim of this study is to find suitable materials for long time afterglow emission under low-dose X-ray irradiation. Fluorine based fluorescent materials were synthesized by high temperature solid phase method hydrothermal method and pyrolysis method respectively. The structure and composition of the samples were analyzed by X-ray diffractometer scanning electron microscope and energy spectrometer. The spectral properties of the sample were analyzed by spectrometer, the afterglow of the sample was analyzed by weak photometer, and the trap position of the sample was analyzed by thermoluminescence metrology. The main contents are as follows: (1) the NaYF_4:Pr~(3) luminescent powder was synthesized by high temperature solid state method. The effects of temperature, raw material and concentration of fluorine source on the phase of NaYF_4 were investigated. The 伪 phase doped with different Pr~(3 concentration and NaYF _ 4 with 尾 phase were prepared. The XRD spectra of 伪 (尾 -NaYF + 4: xPrH3) are analyzed. The X-ray emission spectra, afterglow decay and thermoluminescence curves are characterized. The optimum doping concentration of 伪 -NaYF4 is 3%, and the optimum doping concentration in 尾 -NaYF4 is 1%.Pr~(3). The luminescence and afterglow properties of 伪 -NaYF4 are better than 伪 -NaYF4. Finally, the luminescence of Pr~(3) was regulated by Mg2. The addition of Mg2 was beneficial to the enhancement of 尾 -NaYF4: 1) and the prolongation of afterglow. (2) NaYF_4:Pr~(3) phosphors were synthesized by hydrothermal method. The effects of fluorine concentration and pH value on the phase and morphology of NaYF_4 were investigated. The X-ray emission spectra, afterglow decay and thermoluminescence curves of NaYF_4:Pr~(3 were characterized. The higher the concentration of fluorine source is, the higher the pH value of the rod-like particles is, and the smaller the sample particles are. The emission peak and thermoluminescence peak of NaYF4: P _ (3) were the strongest when the ratio of pH=5 and fluorine yttrium was 1:8, and the afterglow time was also the maximum. (3) NaYF_4:Pr~(3) phosphors were prepared by pyrolysis. The sample is hexagonal phase NaYF4 with pure phase and particle size of 30-40 nm. KYF_4:Pr~(3) phosphors were prepared by hydrothermal method. The X-ray emission spectra, afterglow decay and thermoluminescence curves of KYF_4:Pr~(3 were characterized. The sample is pure phase KYF _ s _ 4 and the particle size is 30-40 nm. Under the excitation of X-ray, the sample has effective luminescence and afterglow.
【学位授予单位】：河北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O482.3

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