ELECTROPOLYMERIZATION OF CARBAZOLE IN MIXED ELECTROLYTE OF TETRAHYDROFURAN AND BORON TRIFLUORIDE DIETHYL ETHERATE
ELECTROPOLYMERIZATION OF CARBAZOLE IN MIXED ELECTROLYTE OF TETRAHYDROFURAN AND BORON TRIFLUORIDE DIETHYL ETHERATE
复制标题
四氢呋喃与三氟化硼二乙醚混合电解液中咔唑的电聚合
作者：
Miao Huaming;Zhang Honglin;Shen Yanyan;Xu Jingkun;Lu Baoyang
本研究的目的是减少电化学聚合过程中常用的三氟化硼乙醚（BFEE）的用量，提高聚合物成膜的稳定性。采用四氢呋喃和四氢呋喃的混合电解质，是因为四氢呋喃可以与四氢呋喃形成比四氢呋喃更稳定的新型配合物，并且可以作为多种芳香族化合物的电聚合溶剂。为了提高混合电解质的离子电导率，引入了Bu_4NBF_4。含18% BFEE（体积）和0.1 mol·L-1 Bu_4NBF_4的THF的离子电导率为1.25×10-3 S·cm-1。在该介质中，通过0.05 mol·L-1咔唑的直接氧化，成功地电合成了高质量的聚咔唑（PCZ）膜。与SCE相比，咔唑在该介质中的氧化电位仅为0.92 V，远低于在含有0.1 mol·L-1 Bu_4NBF_4的乙腈中测定的氧化电位（1.36 V）。该介质制备的PCZ膜具有良好的电化学性能，电导率为7.0×10-3 S·cm-1。形成的PCZ薄膜可以部分溶解在强极性有机溶剂中，如二甲基亚砜。为了脱掺杂，PCZ薄膜用25%的氨水处理3天。紫外可见光谱显示出较宽的吸收带，主要在303 nm处，表明其摩尔质量分布较宽。在荧光光谱中，聚咔唑的发射峰出现在415 nm处，表明PCZ具有蓝光发射特性。对PCZ的FT-IR和1H-NMR光谱研究表明，咔唑的电化学聚合主要发生在3、6个位置，与文献报道的结果吻合较好。热分析表明，用该介质制备的PCZ薄膜具有良好的热稳定性。在该混合电解质中成功电合成了PCZ薄膜，扩展了THF、BFEE和Bu_4NBF_4混合电解质在电化学科学中的应用。
The purpose of this work is to decrease the amount of boron trifluoride diethyl etherate(BFEE) usually used during the electrochemical polymerization and enhance the stability of as-formed polymer films.The mixed electrolyte of tetrahydrofuran(THF) and BFEE was used because THF can form a new complex with BF_3 which is more stable than BFEE and it also can be the solvent for many kinds of aromatic compound which can be electropolymerized.To increase the ionic conductivity of the mixed electrolyte,Bu_4NBF_4 was introduced.The ionic conductivity of THF containing 18% BFEE(by volume) and 0.1 mol·L-1 Bu_4NBF_4 was measured to be 1.25×10-3 S·cm-1.In this medium,high-quality polycarbazole(PCZ) films were electrosynthesized successfully by direct oxidation of 0.05 mol·L-1 carbazole.The oxidation potential of carbazole in this medium was measured to be only 0.92 V versus SCE,which was much lower than that determined in acetonitrile containing 0.1 mol·L-1 Bu_4NBF_4(1.36 V versus SCE).PCZ films obtained from this medium showed good electrochemical behavior,with electrical conductivity of 7.0×10-3 S·cm-1.As-formed PCZ films can be partly dissolved in strong polar organic solvents such as dimethyl sulfoxide.For dedoping,PCZ films were treated with 25% ammonia for 3 days.Then,they were dried at 60℃ for 24 h.The UV-Vis spectra of PCZ showed broader absorption bands mainly at 303 nm,implying wide molar mass distribution.In the fluorescence spectra,the emission peaks of polycarbazole appeared at 415 nm,implying the blue-light-emitting property of PCZ.The FT-IR and 1H-NMR spectral investigations of PCZ indicated that electrochemical polymerization of carbazole mainly occurred at 3,6 positions,in well accordance with the literature reported previously.Thermal analyses indicated that PCZ films prepared from this medium own good thermal stability.The successful electrosyntheses of PCZ films in this mixed electrolyte may extend the applications of this mixed electrolyte of THF,BFEE and Bu_4NBF_4 in the electrochemical science.