Liu Le, Kan Yuanyuan, Gao Ke, Wang Jianxiao, Zhao Min, Chen Hao, Zhao Chengjie, Jiu Tonggang, Jen Alex-K-Y, Li Yuliang
Chinese Academy of Sciences, Qingdao, 266101, P. R. China.
University of Washington, Seattle, WA, 98195-2120, USA.
Adv Mater. 2020 Mar;32(11):e1907604. doi: 10.1002/adma.201907604. Epub 2020 Feb 5.
Morphology tuning of the blend film in organic solar cells (OSCs) is a key approach to improve device efficiencies. Among various strategies, solid additive is proposed as a simple and new way to enable morphology tuning. However, there exist few solid additives reported to meet such expectations. Herein, chlorine-functionalized graphdiyne (GCl) is successfully applied as a multifunctional solid additive to fine-tune the morphology and improve device efficiency as well as reproductivity for the first time. Compared with 15.6% efficiency for control devices, a record high efficiency of 17.3% with the certified one of 17.1% is obtained along with the simultaneous increase of short-circuit current (J ) and fill factor (FF), displaying the state-of-the-art binary organic solar cells at present. The redshift of the film absorption, enhanced crystallinity, prominent phase separation, improved mobility, and decreased charge recombination synergistically account for the increase of J and FF after introducing GCl into the blend film. Moreover, the addition of GCl dramatically reduces batch-to-batch variations benefiting mass production owing to the nonvolatile property of GCl. All these results confirm the efficacy of GCl to enhance device performance, demonstrating a promising application of GCl as a multifunctional solid additive in the field of OSCs.
有机太阳能电池（OSCs）中混合薄膜的形态调控是提高器件效率的关键途径。在各种策略中，固体添加剂被认为是一种实现形态调控的简单新方法。然而，据报道，很少有固体添加剂能达到这样的预期。在此，氯官能化石墨炔（GCl）首次成功地作为多功能固体添加剂用于精细调控形态，提高器件效率和重现性。与对照器件15.6%的效率相比，获得了创纪录的17.3%的高效率，经认证的效率为17.1%，同时短路电流（J）和填充因子（FF）也有所增加，展现了目前最先进的二元有机太阳能电池。薄膜吸收的红移、结晶度的提高、显著的相分离、迁移率的改善以及电荷复合的减少，共同促成了在混合薄膜中引入GCl后J和FF的增加。此外，由于GCl的不挥发性，添加GCl显著降低了批次间的差异，有利于大规模生产。所有这些结果证实了GCl在提高器件性能方面的有效性，表明GCl作为多功能固体添加剂在有机太阳能电池领域具有广阔的应用前景。
