Liu Xingpeng, Ma Ruijie, Wang Yufei, Du Sanshan, Tong Junfeng, Shi Xiaoyan, Li Jianfeng, Bao Xichang, Xia Yangjun, Liu Tao, Yan He
School of Materials Science and Engineering, Gansu Provincial Engineering Research Center for Organic Semiconductor Materials and Application Technology, Lanzhou Jiaotong University, Lanzhou 730070, China.
Department of Chemistry, Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials, Energy Institute and Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration & Reconstruction, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
ACS Appl Mater Interfaces. 2021 Mar 10;13(9):11117-11124. doi: 10.1021/acsami.0c22014. Epub 2021 Feb 26.
Traditional additives like 1,8-diiodooctane and 1-chloronaphthalene were successfully utilized morphology optimization of various polymer solar cells (PSCs) in an active layer, but their toxicity brought by halogen atoms limits their corresponding large-scale manufacturing. Herein, a new nontoxic halogen-free additive named benzyl benzoate (BB) was introduced into the classic PSCs (PTB7-Th:PCBM), and an optimal power conversion efficiency (PCE) of 9.43% was realized, while there was a poor PCE for additive free devices (4.83%). It was shown that BB additives could inhibit PCBM's overaggregation, which increased the interface contact area and formed a better penetration path of an active layer. In addition, BB additives could not only boost the distribution of a PTB7-Th donor at the surface, beneficial to suppressing exciton recombination in inverted devices but also boost the crystallinity of a blend layer, which is conducive to exciton dissociation and charge transport. Our work effectively improved a device performance by using a halogen-free additive, which can be referential for industrialization.
传统添加剂如1,8 - 二碘辛烷和1 - 氯萘已成功用于优化各种聚合物太阳能电池（PSC）活性层的形态，但卤素原子带来的毒性限制了它们相应的大规模制造。在此，一种名为苯甲酸苄酯（BB）的新型无毒无卤添加剂被引入到经典的PSC（PTB7 - Th:PCBM）中，实现了9.43%的最佳功率转换效率（PCE），而无添加剂器件的PCE较差（4.83%）。结果表明，BB添加剂可以抑制PCBM的过度聚集，增加界面接触面积并形成更好的活性层渗透路径。此外，BB添加剂不仅可以促进PTB7 - Th给体在表面的分布，有利于抑制倒置器件中的激子复合，还可以提高共混层的结晶度，这有利于激子解离和电荷传输。我们的工作通过使用无卤添加剂有效地提高了器件性能，可为工业化提供参考。
