He Qiao, Shaw Jessica, Firdaus Yuliar, Hu Xiantao, Ding Bowen, Marsh Adam V, Dumon Alexandre S, Han Yang, Fei Zhuping, Anthopoulos Thomas D, McNeill Christopher R, Heeney Martin
Department of Chemistry and Centre for Processable Electronics, Imperial College London, White City Campus, London W12 0BZ, U.K.
KAUST Solar Center (KSC), Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
Macromolecules. 2023 Jul 26;56(15):5825-5834. doi: 10.1021/acs.macromol.3c00843. eCollection 2023 Aug 8.
Bisthienoazepinedione (BTA) has been reported for constructing high-performing p-type conjugated polymers in organic electronics, but the ring extended version of BTA is not well explored. In this work, we report a new synthesis of a key building block to the ring expanded electron-deficient pentacyclic azepinedione (BTTA). Three copolymers of BTAA with benzodithiophene substituted by different side chains are prepared. These polymers exhibit similar energy levels and optical absorption in solution and solid state, while significant differences are revealed in their film morphologies and behavior in transistor and photovoltaic devices. The best-performing polymers in transistor devices contained alkylthienyl side chains on the BDT unit ( and ) and demonstrated maximum saturation hole mobilities of 0.027 and 0.017 cm V s. Blends of these polymers with PCBM exhibited a best photovoltaic efficiency of 6.78% for -based devices. Changing to a low band gap non-fullerene acceptor (BTP-eC9) resulted in improved efficiency of up to 13.5%. Our results are among the best device performances for BTA and BTTA-based p-type polymers and highlight the versatile applications of this electron-deficient BTTA unit.
双噻吩并氮杂环庚二酮（BTA）已被报道用于在有机电子学中构建高性能的p型共轭聚合物，但BTA的环扩展版本尚未得到充分研究。在这项工作中，我们报道了一种新型的关键构建单元——环扩展缺电子五环氮杂环庚二酮（BTTA）的合成方法。制备了三种BTAA与被不同侧链取代的苯并二噻吩的共聚物。这些聚合物在溶液和固态中表现出相似的能级和光吸收，而它们的薄膜形态以及在晶体管和光伏器件中的行为则显示出显著差异。在晶体管器件中表现最佳的聚合物在BDT单元上含有烷基噻吩基侧链（ 和 ），并表现出最大饱和空穴迁移率分别为0.027和0.017 cm² V⁻¹ s⁻¹。这些聚合物与PCBM的共混物在基于 的器件中表现出最佳光伏效率为6.78%。改用低带隙非富勒烯受体（BTP-eC9）可使效率提高至13.5%。我们的结果是基于BTA和BTTA的p型聚合物的最佳器件性能之一，并突出了这种缺电子BTTA单元的广泛应用。
