Farka Dominik, Greunz Theresia, Yumusak Cigdem, Cobet Christoph, Mardare Cezarina Cela, Stifter David, Hassel Achim Walter, Scharber Markus C, Sariciftci Niyazi Serdar
Linz Institute for Organic Solar Cells (LIOS) Physical Chemistry, Johannes Kepler University Linz, Linz, Austria.
Institute of Solid State Physics, Johannes Kepler University-Linz, Linz, Austria.
Sci Technol Adv Mater. 2021 Dec 23;22(1):985-997. doi: 10.1080/14686996.2021.1961311. eCollection 2021.
We set out to demonstrate the development of a highly conductive polymer based on poly-(3,4-ethylenedithia thiophene) (PEDTT), PEDOTs structural analogue historically notorious for structural disorder and limited conductivities. The caveat therein was previously described to lie in intra-molecular repulsions. We demonstrate how a tremendous >2600-fold improvement in conductivity and metallic features, such as magnetoconductivity can be achieved. This is achieved through a careful choice of the counter-ion (sulphate) and the use of oxidative chemical vapour deposition (oCVD). It is shown that high structural order on the molecular level was established and the formation of crystallites tens of nanometres in size was achieved. We infer that the sulphate ions therein intercalate between the polymer chains, thus forming densely packed crystals of planar molecules with extended π-systems. Consequently, room-temperature conductivities of above 1000 S cm are achieved, challenging those of conventional PEDOT:PSS. The material is in the critical regime of the metal-insulator transition.
我们着手展示一种基于聚（3,4 - 乙撑二硫噻吩）（PEDTT）的高导电聚合物的开发，PEDOT是其结构类似物，历来因结构无序和电导率有限而声名狼藉。其中的问题先前被描述为存在分子内斥力。我们展示了如何实现电导率超过2600倍的巨大提升以及诸如磁导率等金属特性。这是通过精心选择抗衡离子（硫酸根）以及使用氧化化学气相沉积（oCVD）来实现的。结果表明，在分子水平上建立了高度的结构有序性，并形成了尺寸达数十纳米的微晶。我们推断其中的硫酸根离子插入聚合物链之间，从而形成具有扩展π体系的平面分子紧密堆积晶体。因此，实现了高于1000 S cm的室温电导率，对传统的PEDOT:PSS构成挑战。该材料处于金属 - 绝缘体转变的临界区域。
