Co-adsorbed self-assembled monolayer enables high-performance perovskite and organic solar cells

• Published in: Nature communications Vol. 15; no. 1; pp. 7605 - 13
• Main Authors: Li, Dongyang, Lian, Qing, Du, Tao, Ma, Ruijie, Liu, Heng, Liang, Qiong, Han, Yu, Mi, Guojun, Peng, Ouwen, Zhang, Guihua, Peng, Wenbo, Xu, Baomin, Lu, Xinhui, Liu, Kuan, Yin, Jun, Ren, Zhiwei, Li, Gang, Cheng, Chun
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-09-2024; Nature Publishing Group; Nature Portfolio
• Subjects: 140/125; 140/146; 147/135; 147/3; 639/301/299/946; 639/4077/909/4101/4096/946; Acids; Buried structures; Energy; Energy conversion efficiency; Humanities and Social Sciences; Interfaces; Interfacial energy; Maximum power tracking; Microscopy; Monolayers; multidisciplinary; Perovskites; Photovoltaic cells; Science; Science (multidisciplinary); Self-assembled monolayers; Self-assembly; Smoothness; Solar cells; Solar energy; Work functions
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-51760-5

Self-assembled monolayers (SAMs) have become pivotal in achieving high-performance perovskite solar cells (PSCs) and organic solar cells (OSCs) by significantly minimizing interfacial energy losses. In this study, we propose a co-adsorb (CA) strategy employing a novel small molecule, 2-chloro-5-(trifluoromethyl)isonicotinic acid (PyCA-3F), introducing at the buried interface between 2PACz and the perovskite/organic layers. This approach effectively diminishes 2PACz’s aggregation, enhancing surface smoothness and increasing work function for the modified SAM layer, thereby providing a flattened buried interface with a favorable heterointerface for perovskite. The resultant improvements in crystallinity, minimized trap states, and augmented hole extraction and transfer capabilities have propelled power conversion efficiencies (PCEs) beyond 25% in PSCs with a p-i-n structure (certified at 24.68%). OSCs employing the CA strategy achieve remarkable PCEs of 19.51% based on PM1:PTQ10:m-BTP-PhC6 photoactive system. Notably, universal improvements have also been achieved for the other two popular OSC systems. After a 1000-hour maximal power point tracking, the encapsulated PSCs and OSCs retain approximately 90% and 80% of their initial PCEs, respectively. This work introduces a facile, rational, and effective method to enhance the performance of SAMs, realizing efficiency breakthroughs in both PSCs and OSCs with a favorable p-i-n device structure, along with improved operational stability.
Self-assembled monolayers are essential for achieving high performance solar cells by minimizing interfacial energy losses. Here, authors the develop a co-adsorb strategy with a small molecule to provide a favorable heterointerface, realizing high efficiency in p-i-n perovskite and organic devices.