Wang Zhongqiang, Yang Gen, Yin Yabo, Li Kangning, Guan Haowei, Yu Xueliang, Xu Bingshe, Yin Shougen, Hao Yuying
College of Electronic Information and Optical Engineering, Taiyuan University of Technology, Taiyuan, 030024, China.
Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Research Center of Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan, 030024, China.
Small. 2024 Dec;20(49):e2402910. doi: 10.1002/smll.202402910. Epub 2024 Sep 12.
Poly (3-hexylthiophene) (P3HT) is one of the most efficient hole transport layers (HTLs) in perovskite solar cells (PSCs). However, surface and boundary defects in CsPbI, and energy level mismatch between CsPbI and P3HT lead to a low power conversion efficiency (PCE) in P3HT-based CsPbI PSCs. Here, a synergistic strategy with anti-solvent (sec-pentyl alcohol, 2-PA) and passivators (LiX, X = F, Cl, Br, I) is developed to promote the photovoltaic performance of P3HT-based CsPbI PSCs. It is proved that the 2-PA washes away the residual DMF and DMAPbI, and assists the secondary growth of CsPbI crystal. LiX not only can passivate iodine (I) vacancies, but also can reduce energy offset at CsPbI/P3HT interface, accelerating hole extraction process. Finally, an impressive efficiency of 19.26% is obtained due to the synergistic effect of defects passivation and energy alignment, which is 34.4% higher than the 14.32% achieved in Control cell. These findings prove that synergistic strategy of defects passivation and energy alignment is an effective way for realizing high-efficiency in P3HT-based CsPbI PSCs.
聚（3-己基噻吩）（P3HT）是钙钛矿太阳能电池（PSC）中最有效的空穴传输层（HTL）之一。然而，CsPbI中的表面和边界缺陷以及CsPbI与P3HT之间的能级不匹配导致基于P3HT的CsPbI PSC的功率转换效率（PCE）较低。在此，开发了一种使用抗溶剂（仲戊醇，2-PA）和钝化剂（LiX，X = F、Cl、Br、I）的协同策略，以提高基于P3HT的CsPbI PSC的光伏性能。事实证明，2-PA洗去了残留的DMF和DMAPbI，并辅助了CsPbI晶体的二次生长。LiX不仅可以钝化碘（I）空位，还可以减少CsPbI/P3HT界面处的能量偏移，加速空穴提取过程。最后，由于缺陷钝化和能量对准的协同效应，获得了令人印象深刻的19.26%的效率，比对照电池中实现的14.32%高出34.4%。这些发现证明，缺陷钝化和能量对准的协同策略是实现基于P3HT的CsPbI PSC高效率的有效途径。
