Liu Heng, Lu Zhengyu, Zhang Weihai, Wang Jiantao, Lu Zhengli, Dai Quan, Qi Xingnan, Shi Yueqing, Hua Yuhui, Chen Rui, Shi Tingting, Xia Haiping, Wang Hsing-Lin
School of Materials Science and Engineering, Harbin Institute of Technology, Harbin, 150001, P. R. China.
Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, P. R. China.
Adv Sci (Weinh). 2022 Oct;9(29):e2203640. doi: 10.1002/advs.202203640. Epub 2022 Sep 4.
Perovskite solar cells (PSCs) via two-step sequential method have received great attention in recent years due to their high reproducibility and low processing costs. However, the relatively high trap-state density and poor charge carrier extraction efficiency pose challenges. Herein, highly efficient and stable PSCs via a two-step sequential method are fabricated using organic-inorganic (OI) complexes as multifunctional interlayers. In addition to reduce the under-coordinated Pb ions related trap states by forming interactions with the functional groups, the complexes interlayer tends to form dipole moment which can enhance the built-in electric field, thus facilitating charge carrier extraction. Consequently, with rational molecular design, the resulting devices with a vertical dipole moment that parallels with the built-in electric field yield a champion efficiency of 23.55% with negligible hysteresis. More importantly, the hydrophobicity of the (OI) complexes contributes to an excellent ambient stability of the resulting device with 91% of initial efficiency maintained after 3000 h storage.
近年来，通过两步顺序法制备的钙钛矿太阳能电池（PSC）因其高重现性和低加工成本而备受关注。然而，相对较高的陷阱态密度和较差的电荷载流子提取效率带来了挑战。在此，使用有机-无机（OI）配合物作为多功能中间层，通过两步顺序法制备了高效且稳定的PSC。除了通过与官能团形成相互作用来减少与欠配位铅离子相关的陷阱态外，配合物中间层倾向于形成偶极矩，这可以增强内建电场，从而促进电荷载流子的提取。因此，通过合理的分子设计，具有与内建电场平行的垂直偶极矩的所得器件产生了23.55%的冠军效率，滞后现象可忽略不计。更重要的是，（OI）配合物的疏水性有助于所得器件具有出色的环境稳定性，在储存3000小时后仍保持91%的初始效率。
