【作者】 张格平； 李洪光； 郝京诚；

【Author】 Geping Zhang;Hongguang Li;Jingcheng Hao;Key Laboratory of Colloid and Interface Chemistry,Ministry of Education,Shandong University;

【机构】 山东大学胶体与界面化学教育部重点实验室；

【摘要】 荧光共振能量转移(FRET)被广泛应用于生物监测与发光材料的制备等领域。[1]通常,当供体分子的发射光谱与受体分子的激发光谱之间存在光谱重叠,且其距离较近时(<10 nm),可发生FRET现象。[2]通常构筑供体-受体对的方法为利用共价键以及配位键等强相互作用,[3]或是通过自组装的方法,[4]将供体与受体限制在一定的区域内。本文利用发光离子液体和染料分子,构建了一种特殊的供体-受体对。其中,离子液体以萘酰亚胺为发色团,能够发射青色荧光(简称为C2C6-NTf2)。以C2C6-NTf2为溶剂,染料分子DSP作为溶质,制备了一种发射光谱可调的复合离子液体。当通过紫外光激发离子液体中的阳离子时,能量通过共振能量转移的方式传递至受体染料分子,使染料分子发光。利用时间分辨光谱证明了阳离子与染料分子之间的FRET效应。当改变C2C6-NTf2与DSP之间的摩尔比时,两者的荧光强度会发生明显改变,使复合离子液体的发光颜色可调。当两者摩尔比为750:1时,复合离子液体在紫外灯下可出现纯白光的发射,色坐标为(0.30, 0.33)。将该复合离子液体配置成稀溶液,可得到一种具有防伪效果的白光墨水,其字迹在紫外灯下为无色,而在室光下看不到痕迹。由于离子液体拥有较好的热稳定性与粘附性,该复合离子液体还可以负载于紫外芯片,制备白光LED。与传统白光LED制备工艺相比,复合离子液体白光LED的制备过程不需要额外的黏合剂,避免了其对LED发光性能的影响。更多还原

【Abstract】 The principle of fluorescence resonance energy transfer(FRET) was widely used in biological monitoring and manufacture of advanced luminescent materials,[1] which usually occurred between an acceptor and a donor with certain overlap in spectrum and a relative short distance.[2] The traditional way to create D-A pair is by linking the two components with covalent or coordination bonds,[3] or by limiting their distance through self-assembly.[4] Here, we developed an ionic liquid-fluorochorme system as a novel D-A pair. We prepared an ionic liquid 1 with cyan emission, which contains a naphthalimide group. We used 1 as a solvent, to which different fluorochromes were added as solutes. The mixture was then used as an emission-adjustable composite ionic liquid. When excited by UV light, resonance energy transfer occurred between the cations and the fluorochromes, which led to a distinct emission of fluorochromes. This process has been well confirmed by TRES spectrum. When we changed the molar ratio of 1 to the fluorochrome, their fluorescence intensities changed obviously. Interestingly, when we fixed the molar ratio of DSP-to-1 at 1:750, a white emission(0.30, 0.33) was observed. A dilute solution of the composite ionic liquid could be used as anti-counterfeiting ink, which showed white light under UV lamp and was invisible under room light. Due to the high thermostability and viscosity, the composite ionic liquid was a wonderful luminescent coating for UV chip to gain a white emission without any fixative. The method of preparing emission variable materials by means of direct doping D-A pairs was with high potential in luminescent material research.更多还原