Solution-processed nonfullerene bulk-heterojunction (BHJ) polymer solar cells (PSCs), which are composed of polymer donors and organic acceptors, are proven to manifest promising performance and long-term stability. In this concise contribution, bithieno[3,4-c]pyrrole-4,6-dione (BiTPD), which is a TPD derivative but presents a large planar structure and strong electron-withdrawing ability, was used to construct a large-bandgap polymer donor PBiTPD. Results show that the polymer donor PBiTPD realized power conversion efficiency (PCE) as high as 14.2% in fullerene-free BHJ solar cells. Larger ionization potential value, more favorable face-on backbone orientation, and stronger crystallinity were concurrently obtained in PBiTPD. Correspondingly, improved and more balanced charge transportation; less nongeminate and trap-assisted recombination losses; and thus high fill factor (FF) of 67%, short-circuit current density (J_SC) of 25.6 mA·cm^–2, and high open-circuit voltage (V_OC) of 0.83 V were concurrently achieved in PBiTPD-based devices. PBiTPD does clear the way for a novel and promising class of large-bandgap polymer donor candidates.

中文翻译：

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大带隙聚合物供体中的Bithieno [3,4- c ]吡咯-4,6-二酮介导的结晶度指导高效非富勒烯聚合物太阳能电池中的电荷运输和复合。

溶液处理的非富勒烯本体异质结（BHJ）聚合物太阳能电池（PSC）由聚合物供体和有机受体组成，被证明具有良好的性能和长期稳定性。在这种简洁的贡献中，bithieno [3,4- cTPD衍生物] pyrrole-4,6-dione（BiTPD）是TPD衍生物，但具有大的平面结构和很强的吸电子能力，被用于构建大带隙聚合物供体PBiTPD。结果表明，在无富勒烯的BHJ太阳能电池中，聚合物供体PBiTPD实现的功率转换效率（PCE）高达14.2％。同时在PBiTPD中获得更大的电离电势值，更有利的面对主链取向和更强的结晶度。相应地，改进和更加平衡的电荷运输；较少的非成对和陷阱辅助的重组损失；因此，高填充因子（FF）为67％，短路电流密度（J _SC）为25.6 mA·cm ^–2，并且高开路电压（V _OC）在基于PBiTPD的器件中同时达到0.83 V）。PBiTPD确实为新型和有前景的大带隙聚合物供体候选物扫清了道路。