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稀土磷酸盐发光材料的形貌控制及性能研究

时间:2018-05-23 11:32来源:毕业论文
综述了稀土磷酸盐发光材料的性质和常见合成方法,同时也概括性地讨论了发光材料的主要种类、特点、制备方法以及改进的主要途径。然后,通过溶剂热法制备RePO4:Ln3+(Re=Y, La; Re=Eu,

摘要:当下稀土发光材料的应用随处可见。据统计,在世界上新的发明专利中,与稀土有关的发明占专利总数的五分之一。稀土元素之所以被重视和应用,是由于其具有独特的电子层结构。稀土发光材料的优点在于其吸收能力强,转换率高,特别是在可见光区域具有很强的发射能力,且物理化学性质稳定。稀土磷酸盐发光材料是发光领域中最重要的体系之一。当前对稀土磷酸盐研究的主要目的是对其形貌和结构的可控合成,研究形貌-结构-发光性能三者之间的关系,希望获得一种发光效率更高、显色稳定性更好的荧光粉。23218
本论文首先综述了稀土磷酸盐发光材料的性质和常见合成方法,同时也概括性地讨论了发光材料的主要种类、特点、制备方法以及改进的主要途径。然后,通过溶剂热法制备RePO4:Ln3+(Re=Y, La; Re=Eu, Tb),最后利用SEM, XRD和荧光光谱仪等方法对所制备的样品进行表征。此次制备磷酸盐的创新在于首次选用磷酸酯作为磷源,并充当络合剂的角色,观察在正交反应条件下(改变溶剂种类和比例,反应时间,反应物比例,酸碱度等)所制备出磷酸盐的形貌特征。同时研究了Eu3+和Tb3+在RePO4:Ln3+(Re=Y, La; Re=Eu, Tb)两种基质中的发光特点以及制备工艺不同时对Eu3+和Tb3+的发光性质的影响。主要内容可分为如下:
1.    利用溶剂热法,在180℃、恒温条件下,选用磷酸酯作为磷源制备磷酸盐,其中改变反应时间(12~24h),利用X射线衍射仪和透镜电镜对样品进行表征,根据样品形貌择优选择后续最佳反应时间。
2.    利用溶剂热法,在180℃、最佳反应时间、恒温条件下,选用磷酸酯作为磷源,分别以La,Y作为稀土离子源,改变溶剂种类和比例,并与反应物比例进行正交来制备磷酸盐,利用X射线衍射仪和透镜电镜对样品形貌进行表征。
3.    以La,Y的磷酸盐作为基质,分析掺杂Eu3+和Tb3+在这些基质中的发光材料发光特性。
毕业论文关键词:稀土磷酸盐;磷酸酯;溶剂热法;发光材料
The study on morphology and properties of Rare Earth Phosphate Phosphors
Abstract: Rare earth luminescence materials are widely used in our daily life. According to the statistics, inventions relating to rare earth are up to one 5 of the new patent inventions. Rare earth elements are used widely as fluorescent materials because of their characteristic electron structures. The rare earth fluorescent materials have many advantages such as high absorption ability, high transformation ratio, strong emission ability especially at visible light regions, and stable physicochemical properties. The rare earth phosphates are one of the most important parts in the rare earth phosphors as they have been applied widely in illumination industry. Nowadays, the researches about rare earth phosphate are trying to find new ways to prepare phosphor that costs less, luminous efficiency higher, and show color better than before. So it is meaningful that using technology to synthesize rare earth phosphate.
In this dissertation, we review the properties and the synthetic methods of the rare earth phosphates in the first chapter. The main types, characteristics, preparation, and improvement of phosphors are also discussed. Then RePO4:Ln3+(Re=Y, La; Re=Eu, Tb) are synthesized by solvothermal method, the samples are tested by XRD, TEM and fluorescence spectrometer. The innovation lies in the preparation of phosphate as the first choice of phosphate phosphorus source. And to act as a complexing agent, observed under crossed reaction conditions (solvent species, and changes the ratio, reaction time, ratio of reactants, pH, etc.) of the morphology of the prepared phosphate. Also studied Eu3+ and Tb3+ in RePO4:Ln3+(Re=Y, La; Re=Eu, Tb) luminescent characteristics and the impact of two matrix preparation is not the same for Eu3+ and Tb3+ luminescence properties. Main content can be pided as follows: 稀土磷酸盐发光材料的形貌控制及性能研究:http://www.751com.cn/huaxue/lunwen_16174.html
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