【作者】 李庆润； 陈晓；

【Author】 Qingrun Li;Xiao Chen;Key Laboratory of Colloid and Interface Chemistry,Shandong University,Ministry of Education;

【机构】 山东大学胶体与界面化学教育部重点实验室；

【摘要】 本文报道了用部分两亲铕β-二酮络合物(Eu(III))在质子性离子液体硝酸乙基铵(EAN)中与1-十二烷基-3-甲基咪唑溴化物[C12mim]Br共组装形成的发光囊泡和溶致液晶。由于Eu(III)和咪唑基团及溶剂间的相互作用改变了[C12mim]Br的临界堆积参数,最终诱导形成了囊泡。与Eu(III)溶液相比,形成的囊泡聚集体表现出增强的荧光强度和寿命。同时,在较高[C12mim]Br浓度下,可以形成发光性质更好的六角相溶致液晶。荧光物理参数证实:含Eu(III)的有序聚集体可有效提高配体的能量转换效率;溶致液晶中更好的发光性能源于其对Eu(III)更强的稳定和束缚作用。本文结果不仅扩展了在离子液体中构建含镧系元素发光软材料的策略,而且为更好地理解有序聚集体对发光性能的影响提供了参考。更多还原

【Abstract】 In this work, the co-assembling of luminescent vesicle and lyotropic liquid crystal(LLC) in a protic ionic liquid, ethylammonium nitrate(EAN), by a 1-dodecyl-3-methylimidazolium bromide([C12 mim]Br) and a partially amphiphilic europium β-diketonate complex(Eu(III)) with a [C12 mim]+ cation as the counter ion. It was the interaction between Eu(III) and imidazolium group that changed the critical packing parameter of [C12 mim]Br, which finally resulted in the occurrence of vesicle. The obtained vesicle aggregates exhibited enhanced fluorescence intensity and lifetime compared to those of Eu(III) solution. Meanwhile, a hexagonal LLC phase with better fluorescence properties was found at higher [C12 mim]Br concentration. The obtained photophysical data confirmed that the order degree of Eu(III)-containing aggregates could effectively increase the energy transition efficiency of ligands. The better luminescent properties of LLC were resulted from the stronger stabilizing and binding effects on Eu(III) in LLC than that in vesicle. The results presented here will not only expand the strategy of constructing lanthanide-containing luminescent soft materials in ionic liquids, but also provide a reference to better understand the effect of organized aggregates on luminescence properties.更多还原