Conductive thiophene-based polymers have garnered great attention for use in organic electron materials such as electrochromic and thermoelectric materials. However, they suffer from poor electron transport properties and long-term stability, leading to limited development eventually. Here, we proposed a strategy of functionalized thiophene-based polymers with oligo(ethylene glycol) or alkyl side chains and synthesized a series of poly(3,4-ethylenedioxy bithiophene)s (PEDTs) to tune their electrochromic and thermoelectric properties. An alkyl group bearing electronic ability at the thiophene ring effectively achieved a large increase in the electrical conductivity with nearly invariable Seebeck coefficient, resulting in an enhancement by 1 order of magnitude for the thermoelectric power factor. Moreover, the electrochromic properties of functionalized PEDTs gained an effective improvement in the optical contrast and coloration efficiency as well as stability with multicolor changes between neutral and oxidized states. The functionalized PEDTs can be proposed as an alternative strategy to tune the electrochromic and thermoelectric properties for organic polymer materials.

中文翻译：

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用于调节电致变色和热电性能的功能化聚（3,4-乙撑二氧联噻吩）薄膜

导电噻吩基聚合物在有机电子材料（例如电致变色和热电材料）中的使用引起了极大的关注。但是，它们具有较差的电子传输性能和长期稳定性，最终导致有限的开发。在这里，我们提出了一种具有低聚乙二醇或烷基侧链的功能化噻吩基聚合物的策略，并合成了一系列聚（3,4-乙撑二氧基联噻吩）（PEDT），以调节其电致变色和热电性能。在噻吩环上具有电子能力的烷基有效地实现了电导率的大幅提高，且塞贝克系数几乎不变，从而使热电功率因数提高了1个数量级。而且，功能化PEDT的电致变色性能在光学对比度和着色效率以及中性和氧化态之间多色变化的稳定性方面获得了有效的改善。可以提出功能化的PEDT作为替代策略，以调节有机聚合物材料的电致变色和热电性能。