Crosslinkable and Chelatable Organic Ligand Enables Interfaces and Grains Collaborative Passivation for Efficient and Stable Perovskite Solar Cells

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 18; no. 22; pp. e2201820 - n/a
• Main Authors: Ma, Zongwen, Yu, Runnan, Xu, Zhiyang, Wu, Guangzheng, Gao, Huaizhi, Wang, Ruyue, Gong, Yongshuai, Yang, Jing, Tan, Zhan'ao
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01-06-2022
• Subjects: chemical anchoring; Collaboration; collaborative interface‐grain engineering; Commercialization; Crosslinking; Crystal defects; Degradation; Electron transport; Energy conversion efficiency; Freezing; Grain boundaries; in situ crosslinking; Interface stability; Interfaces; Ligands; Moisture effects; Nanotechnology; perovskite solar cells; Perovskites; Phase transitions; Photovoltaic cells; Solar cells; stability; Thermal stability; Tin dioxide; collaborative interface-grain engineering; in situ crosslinking; chemical anchoring; perovskite solar cells; stability
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202201820

The organic–inorganic halide perovskite solar cell (PerSC) is the state‐of‐the‐art emerging photovoltaic technology. However, the environmental water/moisture and temperature‐induced intrinsic degradation and phase transition of perovskite greatly retard the commercialization process. Herein, a dual‐functional organic ligand, 4,7‐bis((4‐vinylbenzyl)oxy)‐1,10‐phenanthroline (namely, C1), with crosslinkable styrene side‐chains and chelatable phenanthroline backbone, synthesized via a cost‐effective Williamson reaction, is introduced for collaborative electrode interface and perovskite grain boundaries (GBs) engineering. C1 can chemically chelate with Sn4+ in the SnO2 electron transport layer and Pb2+ in the perovskite layer via coordination bonds, suppressing nonradiative recombination caused by traps/defects existing at the interface and GBs. Meanwhile, C1 enables in situ crosslinking via thermal‐initiated polymerization to form a hydrophobic and stable polymer network, freezing perovskite morphology, and resisting moisture degradation. Consequently, through collaborative interface‐grain engineering, the resulting PerSCs demonstrate high power conversion efficiency of 24.31% with excellent water/moisture and thermal stability. The findings provide new insights of collaborative interface‐grain engineering via a crosslinkable and chelatable organic ligand for achieving efficient and stable PerSCs.
A dual‐function of crosslinking and chelating strategy is established to dramatically eliminate the defects and enhance the long‐term stability of perovskite solar cells (PerSCs) via a crosslinkable organic ligand (C1). Though chemical anchoring and in situ crosslinking of C1, electrode interfaces, and perovskite grains are collaboratively optimized, resulting in highly efficient and stable PerSCs.