Keerthi Ashok, Waliszewski Witold, An Cunbin, Jaber Abdullah, Xia Debin, Müllen Klaus, Pisula Wojciech, Marszalek Tomasz, Baumgarten Martin
Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
School of Physics and Astronomy Condensed Matter Physics Group, The University of Manchester, M13 9PL Manchester, U.K.
ACS Omega. 2018 Jun 18;3(6):6513-6522. doi: 10.1021/acsomega.8b00836. eCollection 2018 Jun 30.
Four derivatives of dithieno[2,3-;2',3'-']benzo[1,2-;3,4-']dithiophene () have been synthesized to investigate the correlation between molecular structure, thin-film organization, and charge-carrier transport. Phenyl or thiophene end-capped derivatives at alpha positions of the outer thiophenes of present vastly different optoelectronic properties in comparison with bay-position alkyl-chain-substituted , which was additionally confirmed by density functional theory simulations. The film morphology of the derivatives strongly depends on alkyl substituents, aromatic end-caps, and substrate temperature. Field-effect transistors based on derivatives with bay-substituted alkyl chains show the best performance within this studied series with a hole mobility up to 0.75 cm/V s. Attachment of aromatic end-caps disturbs the ordering, limiting the charge-carrier transport. Higher substrate temperature during deposition of the derivatives with aromatic end-caps results in larger domains and improved the transistor mobilities but not beyond the alkylated .
已合成了二噻吩并[2,3-;2',3'-']苯并[1,2-;3,4-']二噻吩（）的四种衍生物，以研究分子结构、薄膜组织和电荷载流子传输之间的相关性。与海湾位置烷基链取代的相比，在外部噻吩α位带有苯基或噻吩封端的衍生物具有截然不同的光电特性，密度泛函理论模拟进一步证实了这一点。衍生物的薄膜形态强烈取决于烷基取代基、芳香族封端和衬底温度。基于带有海湾取代烷基链的衍生物的场效应晶体管在该研究系列中表现最佳，空穴迁移率高达0.75 cm²/V·s。芳香族封端的附着会扰乱有序排列，限制电荷载流子传输。在沉积带有芳香族封端的衍生物时提高衬底温度会导致更大的畴，并改善晶体管迁移率，但不会超过烷基化的。
