An imidazolium-based ionic liquid (IL) modified triphenylamine derivative, namely 1-(4-((4-(diphenylamino)benzoyl) oxy)butyl)-3-methyl imidazole tetrafluoroborate (TPAC₆IL-BF₄), was designed and synthesized, and further applied with 3,4-ethylene dioxythiophene (EDOT) to prepare conjugated copolymer P(EDOT:TPAC₆IL-BF₄) via electrochemical polymerization. The cyclic voltammetry curves show that the copolymer P(EDOT:TPAC₆IL-BF₄) possesses two pairs of redox peaks, which should be ascribed to the redox behaviors of EDOT and triphenylamine. The ultraviolet-visible (UV-Vis) absorption spectrum of P(EDOT:TPAC₆IL-BF₄) exhibits one maximum absorption peak at 580 nm and a small shoulder characteristic peak at 385 nm under neutral state which are assigned to π-π* conjugated structure of EDOT and triphenylamine. After being applied at the positive voltage, the copolymer color changes from dark blue to light blue, which is close to the color of poly(3,4-ethylenedioxythiophene) (PEDOT). Surprisingly, the copolymer P(EDOT:TPAC₆IL-BF₄) shows shorter switching time of 0.37 s, 0.30 s at 580 nm and 0.38 s, 0.45 s at 1100 nm compared with PEDOT. It is more intriguing that the copolymer P(EDOT:TPAC₆IL-BF₄) exhibits electrochromism even in free supporting electrolyte. The results confirm that the existence of imidazolium-based ionic liquid has an improvement on the ion diffusion properties and the switching time of conjugated polymer, which may provide a potential direction for the preparation of high-performance electrochromic materials.

设计并设计了咪唑基离子液体（IL）改性的三苯胺衍生物，即1-（4-（（4-（（二苯氨基）苯甲酰基）氧基）丁基）-3-甲基咪唑四氟硼酸酯（TPAC ₆ IL-BF ₄），合成，并进一步与3,4-乙撑二氧噻吩（EDOT）一起使用，通过电化学聚合反应制备共轭共聚物P（EDOT：TPAC ₆ IL-BF ₄）。循环伏安曲线表明，共聚物P（EDOT：TPAC ₆ IL-BF ₄）具有两对氧化还原峰，这应归因于EDOT和三苯胺的氧化还原行为。P（EDOT：TPAC ₆ IL-BF ₄的紫外-可见（UV-Vis）吸收光谱）在中性状态下在580 nm处显示一个最大吸收峰，在385 nm处显示一个小的肩峰特征峰，这与EDOT和三苯胺的π-π *共轭结构有关。在施加正电压后，共聚物的颜色从深蓝色变为浅蓝色，接近于聚（3,4-乙撑二氧噻吩）（PEDOT）的颜色。出乎意料的是，与PEDOT相比，共聚物P（EDOT：TPAC ₆ IL-BF ₄）显示出更短的切换时间，分别为580nm处的0.37s，0.30s和1100nm处的0.38s，0.45s。更有趣的是，共聚物P（EDOT：TPAC ₆ IL-BF ₄）即使在自由支持的电解质中也表现出电致变色现象。结果证实，咪唑基离子液体的存在改善了共轭聚合物的离子扩散性能和转换时间，这可能为制备高性能电致变色材料提供了潜在的方向。