Title: Electrochemical Doping in Ordered and Disordered Domains of Conjugated Polymers Show Chinese title

Title: 共轭聚合物有序和无序畴中的电化学掺杂

Abstract: Conjugated polymers are increasingly used as organic mixed ionic-electronic conductors in electrochemical devices for neuromorphic computing, bioelectronics and energy harvesting. The design of efficient applications relies on high electrochemical doping levels, high electronic conductivity, fast doping/dedoping kinetics and high ionic uptake. In this work, we establish structure-property relations and demonstrate how these parameters can be modulated by the co-existence of order and disorder. We use in-situ time-resolved spectroelectrochemistry, resonant Raman and terahertz conductivity measurements to investigate the electrochemical doping in the different morphological domains of poly(3-hexylthiophene). Our main finding is that bipolarons are found preferentially in disordered polymer regions, where they are formed faster and are thermodynamically more favoured. On the other hand, polarons show a preference for ordered domains, leading to drastically different bipolaron/polaron ratios and doping/dedoping dynamics in the distinct regions. We evidence a significant enhancement of the electronic conductivity when bipolarons start being formed in the disordered regions, while the presence of bipolarons in the ordered regions is detrimental for transport. Our study provides significant advances in the understanding of the impact of morphology on the electrochemical doping of conjugated polymers and the induced increase in conductivity. Show Chinese abstract

Abstract: 共轭聚合物在神经形态计算、生物电子学和能量收集的电化学器件中作为有机混合离子-电子导体被越来越多地使用。 高效应用的设计依赖于高电化学掺杂水平、高电子电导率、快速的掺杂/去掺杂动力学和高离子吸收能力。 在本工作中，我们建立了结构-性能关系，并展示了这些参数如何通过有序和无序的共存进行调节。 我们使用原位时间分辨光谱电化学、共振拉曼和太赫兹电导率测量来研究聚(3-己基噻吩)不同形态区域中的电化学掺杂。 我们的主要发现是，双极子优先存在于无序聚合物区域，在那里它们形成得更快且热力学上更有利。 另一方面，极化子则倾向于有序区域，导致不同区域中的双极子/极化子比率和掺杂/去掺杂动力学存在显著差异。 我们证明了当双极子在无序区域开始形成时，电子电导率显著增强，而双极子在有序区域的存在则对传输有害。 我们的研究在理解形态对共轭聚合物电化学掺杂的影响以及由此引起的电导率增加方面取得了重要进展。