Data underlying the publication: Stochastic electrical detection of single ion-gated semiconducting polymers

Semiconducting polymer chains constitute the building blocks for a wide range of electronic materials and devices. However, most of their electrical characteristics at single molecule level have received little attention. Elucidating these properties could help understanding performance limits and enabling new applications. Here we exploit coupled ionic-electronic charge transport to measure the quasi-one-dimensional electrical current through single, long conjugated polymer chains as they form transient contacts with electrodes separated by ~10 nm. Fluctuations between internal conformations of the individual polymers are resolved as abrupt, multi-level switches in the electrical current. This behavior is consistent with our theoretical simulations based on the worm-like-chain model for semi-flexible polymers. In addition to probing the intrinsic properties of single semiconducting polymer chains, our results provide an unprecedented window into the dynamics of random-coil polymers and enable the use of semiconducting polymers as electrical labels for single-molecule (bio)sensing assays.

半导体聚合物（semiconducting polymer）链是各类电子材料与器件的结构基元。然而，其单分子层面的绝大多数电学特性尚未得到足够关注。阐明这类特性有助于厘清其性能极限并开拓全新应用场景。本研究借助离子-电子耦合电荷输运技术，对单根长共轭聚合物（conjugated polymer）链与间距约10纳米的电极形成瞬态接触时的准一维电流开展了测量。单根聚合物链的内部构象涨落，会表现为电流信号中突变的多阶开关行为。该行为与基于半柔性聚合物蠕虫链模型（worm-like-chain model）的理论模拟结果相符。除了表征单根半导体聚合物链的本征特性外，本研究结果还为无规卷曲聚合物（random-coil polymer）的动力学研究提供了前所未有的视角，同时使得半导体聚合物可作为电学标记物应用于单分子（生物）传感检测实验。