噻吩-咔唑-苯衍生物的设计、合成及电致变色性质

Synthesis and Electrochromic Properties of Thiophene-carbazol-benzene Derivativies

以苯和二联苯单元为核,分别在其1,4位和4,4'(对位)引入噻吩-咔唑单元,设计合成了9,9'-(1,4-亚苯基)双[3,6-双(2-噻吩)]-9-氢-咔唑(BTCPh)和9,9'-[1,1'-联苯基]-4,4'-二取代基双[3,6-双(2-噻吩)]-9-氢-咔唑(BTCBPh)2种化合物;再通过电化学聚合得到相应的交联结构聚合物,分别为聚9,9'-(1,4-亚苯基)双[3,6-双(2-噻吩)]-9-氢-咔唑(p BTCPh)和聚9,9'-[1,1'-联苯基]-4,4'-二取代基双[3,6-双(2-噻吩)]-9-氢-咔唑(p BTCBPh)薄膜.利用循环伏安法(CV)、多电位阶跃、紫外-可见-近红外(UV-Vis-NIR)吸收光谱和扫描电子显微镜(SEM)等手段对其进行了表征与电化学性能测试.结果表明,2种聚合物均表现出良好的电化学性质、相似的颜色变化、较高的光学对比度及电化学循环稳定性等优异的电致变色性质.p BTCPh聚合物薄膜比p BTCBPh表现出更快的响应速度,这可能是由于前者具有更加均匀规整的堆积结构,有利于变色过程中的离子嵌入与脱出所致.

The central phenyl and biphenyl groups were introduced into the N-positions of two thiophenecarbazole structures to form the desired 9,9＇-（ 1,4-phenylene） bis[3,6-di-2-thienyl]-9 H-carbazole（ BTCPh）and 9,9＇-[1,1＇-biphenyl]-4,4＇-diylbis[3,6-di-2-thienyl]-9 H-carbazole（ BTCBPh）,respectively. The obtained BTCPh and BTCBPh were electrochemically polymerized to generate the corresponding polymers,poly9,9＇-（ 1,4-phenylene） bis[3,6-di-2-thienyl]-9 H-carbazole（ p BTCPh） and poly 9,9＇-[1,1＇-biphenyl]-4,4＇-diylbis[3,6-di-2-thienyl]-9 H-carbazole（ p BTCBPh）,which might possess the cross-linked structure. The polymers were investigated by different character methods,such as cyclic voltammetry,multi-current step,ultraviolet visible near infrared absorption spectrum,scanning electron microscope and so on. The results showed that both of p BTCPh and p BTCBPh polymers exhibited excellent electrochromic properties with similar color changes,high optical contrast and good electrochemical cycle stability. And p BTCPh polymer film showed the faster color switching speed than p BTCBPh,which was ascribed to the possible more uniform stack structure in p BTCPh film. The uniform stack structure was beneficial to the fast ion inserting/deserting behavior in the electrochromic process.