Cai Ning, Li Fengzhu, Chen Yatong, Luo Ruixi, Hu Tonghui, Lin Francis, Yiu Shek-Man, Liu Danjun, Lei Dangyuan, Zhu Zonglong, Jen Alex K-Y
School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, China.
Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, 999077, Hong Kong, Hong Kong.
Angew Chem Int Ed Engl. 2021 Sep 6;60(37):20437-20442. doi: 10.1002/anie.202107020. Epub 2021 Aug 6.
Delicately designed dopant-free hole-transporting materials (HTMs) with ordered structure have become one of the major strategies to achieve high-performance perovskite solar cells (PSCs). In this work, we report two donor-π linker-donor (D-π-D) HTMs, N01 and N02, which consist of facilely synthesized 4,8-di(n-hexyloxy)-benzo[1,2-b:4,5-b']dithiophene as a π linker, with 10-bromohexyl-10H-phenoxazine and 10-hexyl-10H-phenoxazine as donors, respectively. The N01 molecules form a two-dimensional conjugated network governed by C-H⋅⋅⋅O and C-H⋅⋅⋅Br interaction between phenoxazine donors, and synchronously construct a three-dimension lamellar structure with the aid of interlaminar π-π interaction. Consequently, N01 as a dopant-free small-molecule HTM exhibits a higher intrinsic hole mobility and more favorable interfacial properties for hole transport, hole extraction and perovskite growth, enabling an inverted PSC to achieve a very impressive power conversion efficiency of 21.85 %.
精心设计的具有有序结构的无掺杂空穴传输材料（HTMs）已成为实现高性能钙钛矿太阳能电池（PSCs）的主要策略之一。在这项工作中，我们报道了两种供体-π-连接体-供体（D-π-D）HTMs，即N01和N02，它们由易于合成的4,8-二（正己氧基）-苯并[1,2-b:4,5-b']二噻吩作为π连接体，分别以10-溴己基-10H-吩恶嗪和10-己基-10H-吩恶嗪作为供体。N01分子形成了一个二维共轭网络，由吩恶嗪供体之间的C-H⋅⋅⋅O和C-H⋅⋅⋅Br相互作用控制，并借助层间π-π相互作用同步构建了三维层状结构。因此，N01作为一种无掺杂小分子HTM，表现出更高的本征空穴迁移率以及对空穴传输、空穴提取和钙钛矿生长更有利的界面性质，使得倒置PSC能够实现高达21.85%的令人印象深刻的功率转换效率。
