SiO_2包覆上转换发光材料Na(Y_(0.57)Yb_(0.39)Er_(0.04))F_4的研究

The Study of Up-converting Phosphor Material Na(Y_(0.57)Yb_(0.39)Er_(0.04))F_4 Surface Coated with Silica

近年来上转换发光材料在荧光标记中由于其独特的优势引起人们极大的关注。但在某些应用过程中出现分散性不好和易于沉降的缺点,影响了它作为荧光探针的应用。为了改善这种状况,制备了一种由二氧化硅包覆的上转换发光材料。并用红外光谱、扫描电镜、透射电镜等手段对材料进行了表征。结果表明二氧化硅已经包覆到上转换材料上,并且在实验条件下制备的产物粒径较小,颗粒为均匀的球形,二氧化硅包覆层厚度大约为10 nm。实验还对包覆条件进行了探索,得到最佳实验条件为:试验选用正丁醇作溶剂,体积为100 mL;用氨水作分散剂;催化剂水和正硅酸乙酯的量的比应是1∶1,反应时间为40 m in。

Up-converting phosphors material （UPM） is the material that exhibits two-photon anti-Stokes luminescence by up-converting infrared to visible light. The material we used is a kind of UCM that emits green light when excited by 980 nm light. In fluorescent labels, UPM have many advantages： 1. Permanent, strong, anti-Stokes emission of discrete wavelengths; 2. unmatched contrast in biological specimens due to the absence of autofluorescence upon excitation with IR light; 3. simultaneous detection of multiple target analytes; 4. low-cost microscope modifications. Recently there is growing interest in studying UPM because of their most promising use as fluorescent labels for the sensitive detection of cell and tissue antigens. But the up-converting phosphors materials unmodified are easy to reunite and deposit, so they can＇t directly apply to fluorescent labels reporters. To enlarge the usages of up-converting phosphors material （UPM） in fluorescent labels and biological check, we prepared a kind of UPM with surface coated by silica and then signified this kind of material. The particle size of the product is very uniform and the particle shape of product keeps spherical. The thickness of silica is about 10 nm and the luminescence intensity has greatly increased. The paper also did a lot of research about the conditions of up-conversion phosphors material cladding by silicon dioxide, and found out the best conditions. We selected n-butyl alcohol as solvent and used ammonia water as dispersing agent. The volume of solvent is 100 mL. The mole ratio is 1：1 between tetraethylorthosilicate and water, and reaction time is 40 min. After the surface coated, the up-conversion phosphors material＇s dispersibility on aqueous solutions is better than before, and the stability is strengthened. This paper is the first step to modify the UPM, then we will modify the UPM with amino-group. We expect that the new material has better application foreground in biochip field.