Tb(Ⅲ)-PNVA-co-PSt纳米微球的制备及其光学性能研究

Synthesis and Spectroscopic Properties of Tb(Ⅲ)-PNVA-co-PSt Nanospheres

以KPS为引发剂,一定比例的水/乙醇混合物为反应介质,采用改进的无皂种子乳液聚合方法,制得了以聚苯乙烯(PSt)为核、聚N-乙烯基乙酰胺(PNVA)为壳的单分散纳米级PNVA-co-PSt共聚微球,并使Tb3+离子与纯化后的PNVA-co-PSt微球进行配位,得到了Tb(Ⅲ)-PN-VA-co-PSt配合物微球。利用扫描电子显微镜、Zeta-电位、红外光谱、紫外光谱及荧光光谱对微球及其配合物进行了表征。结果表明:PNVA-co-PSt微球具有良好的球形结构;Tb3+离子与PNVA-co-PSt微球之间确实存在配位作用,大大增强了配合物微球在紫外区的吸光性能,且在PNVA-co-PSt微球和Tb3+之间发生了有效的F rster能量传递,使得位于490,545以及583 nm处的Tb3+的特征发射明显增强。配合物微球的荧光光谱峰形尖锐,说明其单色性较好,是一种有应用潜力的发光新材料。

The poly （ N-vinylacetamide）-co-polystyrene （PNVA-co-PSt） nanospheres with PSt as core and PNVA as shell were synthesized by emulslfier-free seed emulsion polymerization using KPS as initiator in ethanol-water mixed solvents. The Tb （Ⅲ）-PNVA-co-PSt nanospheres were obtained based on the coordinate reaction between PNVA-co-PSt nanospheres and Tb^3＋ ions. The properties of the PNVA-co-PSt nanospheres and Tb （Ⅲ）-PNVA-co-PSt nanospheres were characterized by scanning electron microscopy, Zeta-potential, FTIR spectroscopy, UV spectroscopy and fluorescence spectroscopy. It was found that the absorption capability of Tb （ Ⅲ ）-PNVA-co-PSt nanospheres for the ultraviolet ray was improved greatly, and the efficient Forster energy transfer from PNVA-co-St nano- spheres to Tb^3＋ ions existed. Therefore, the relative intensity of Tb^3＋ ions at characteristic emission peaks at 490, 545 and 585 nm were strengthened enormously. It showed that the Tb （Ⅲ）-PNVA-co-PSt nano- sphere was a new and application-potential material with a very high caloric purity for its sensitivity emission spectrum.