Poly(thieno[3,4-b]-1,4-oxathiane): Medium Effect on Electropolymerization and Electrochromic Performance

详细信息    查看全文

• 作者：Zhipeng Wang ; Jingkun Xu ; Baoyang Lu ; Shimin Zhang ; Leiqiang Qin ; Daize Mo ; Shijie Zhen
• 刊名：Langmuir
• 出版年：2014
• 出版时间：December 30, 2014
• 年：2014
• 卷：30
• 期：51
• 页码：15581-15589
• 全文大小：595K
• ISSN：1520-5827

文摘

The asymmetrical sulfur analog of 3,4-ethylenedioxythiophene (EDOT), thieno[3,4-b]-1,4-oxathiane (EOTT), was synthesized, and its electropolymerization was comparatively investigated by employing different solvent鈥揺lectrolyte systems (room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (BmimPF₆), CH₂Cl₂鈥揃u₄NPF₆, and CH₂Cl₂鈥揃mimPF₆). Further, the effect of solvents and supporting electrolytes on the structure, morphology, electrochemical, electronic, and optical properties and electrochromic performance of the obtained poly(thieno[3,4-b]-1,4-oxathiane) (PEOTT) films were minutely studied. PEOTT film with a band gap (E_g) of about 1.6 eV could be facilely electrodeposited in all the solvent-electrolytes and displayed excellent electroactivity, outstanding redox stability in a wide potential window, and improved thermal stability. Cyclic voltammetry showed that EOTT could be electropolymerized at a lower oxidation potential in BmimPF₆ (鈭?.0 V vs Ag/AgCl) due to several advantanges of RTIL BmimPF₆ itself, such as high intrinsic conductivity and mild chemical conditions, etc., and the resulting PEOTT film exhibited compact morphology with better electroactivity and stability and higher electrical conductivity. On the other hand, PEOTT films from all the sovent-electrolytes also showed the electrochromic nature by color changing from gray blue to green, and further kinetic studies revealed that PEOTT had decent contrast ratios (36%), higher coloration efficiencies (212 cm²/C in BmimPF₆), low switching voltages, moderate response time (1.2 s), excellent stability, and color persistence. From these results, PEOTT provides more plentiful electrochromic colors and holds promise for display applications.