作　　者： ; ; ; ;

机构地区： 深圳大学化学与化工学院

出　　处： 《深圳大学学报（理工版）》 2011年第1期41-46,共6页

摘　　要： 以对二甲苯为连续相,水为分散相,聚(氧乙烯)-聚(氧丙烯)-聚(氧乙烯)嵌段聚合物为表面活性剂,制备ZnSe和ZnMnSe量子点.在量子点表面覆盖一层Zn(OH)2使其发生钝化,再加水引起相分离,选择合适的有机溶剂可从反相微乳液中成功分离出上述量子点,分离后的量子点保持荧光特性且量子点荧光有显著增强.经11-巯基十一烷酸表面修饰,分离的量子点可分散在水中形成透明溶液.采用X-射线衍射、透射电镜、动态激光光散射和荧光光度计表征晶体结构、形貌、尺寸分布和荧光特性,讨论了使量子点稳定的表面保护机理.研究结果表明,嵌段聚合物分子吸附在量子点表面,阻碍了其氧化进程,表面钝化可修补晶体部分缺陷,使分离的量子点荧光增强,稳定期达数月之久. The successful extractions of ZnMnSe as well as ZnSe quantum dots （QDs） from a reverse micelle template were reported.The recovered QDs kept their functionality with distinct enhancement in photoluminescence.After being coated with a possible layer of Zn（OH）2 within the template,the QDs were extracted from the template by adding water to induce phase transition and employing specific organic solvent.Thereafter,the extracted QDs were capped with mercapto-undecanoic acid for dispersion in water to render crystal clear solution.Analytical techniques such as X-ray diffraction,transmission electron microscopy,dynamic light scattering,and fluorometer were employed to characterize the crystal structure,morphology,average particle size,and photoluminescence of the samples.The mechanism of the surface protection towards QDs was investigated and discussed.A mechanism was proposed as block copolymer molecular being adsorbed to the QDs surface that retards the oxidation process of QDs during the extraction.Consequently,the extracted QDs demonstrated invariable photoluminescence and consistent stability for months.

关 键 词： 分离与提纯 量子点 光致发光 反相微乳液 嵌段聚合物 过渡金属掺杂 表面修饰 表面钝化

领　　域： [理学]