Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.
University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
Chemphyschem. 2019 Oct 16;20(20):2696-2701. doi: 10.1002/cphc.201900309. Epub 2019 May 22.
Tandem-junction organic solar cells require solar cells with visible light photo-response as front cells, in which an open-circuit voltage (V ) above 1.0 V is highly demanded. In this work, we are able to develop electron acceptors to fabricate non-fullerene organic solar cells (NFOSCs) with a very high V of 1.14 V. This was realized by designing perylene bisimide (PBI)-based conjugated materials fused with benzodithiophene, in which Cl and S atom were introduced into the molecules in order to lower the frontier energy levels. The fused structures can reduce the aggregation of PBI unit and meanwhile maintain a good charge transport property. The new electron acceptors were applied into NFOSCs by using Cl and S substituted conjugated polymers as electron donor, in which an initial power conversion efficiency of 6.63 % and a high V of 1.14 V could be obtained. The results demonstrate that the molecular design by incorporating Cl and S atom into electron acceptors has great potential to realize high performance NFOSCs.
串联结有机太阳能电池需要具有可见光光响应的太阳能电池作为前电池，其中要求开路电压 (V ) 高于 1.0V。在这项工作中，我们能够开发电子受体来制造具有非常高的 V 值为 1.14V 的非富勒烯有机太阳能电池 (NFOSC)。这是通过设计基于苝二酰亚胺 (PBI) 的共轭材料与苯并二噻吩融合来实现的，其中在分子中引入了 Cl 和 S 原子以降低前沿能级。融合结构可以减少 PBI 单元的聚集，同时保持良好的电荷传输性能。新的电子受体通过使用 Cl 和 S 取代的共轭聚合物作为电子给体应用于 NFOSC，其中可以获得 6.63%的初始功率转换效率和 1.14V 的高 V 值。结果表明，通过将 Cl 和 S 原子掺入电子受体中的分子设计具有实现高性能 NFOSC 的巨大潜力。
