Zhang Nan, An Yidan, Yao Qin, Zou Guangruixing, Zhou Ning, Wu Ye, Chen Desui, Lin Francis R, Jen Alex K-Y, Yip Hin-Lap
Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China.
Center of Super-Diamond and Advanced Films, City University of Hong Kong, Kowloon, Hong Kong 999077, China.
ACS Appl Mater Interfaces. 2025 May 7;17(18):26959-26967. doi: 10.1021/acsami.5c03878. Epub 2025 Apr 24.
The PEDOT:PSS has been utilized extensively as a hole transport layer (HTL) in organic solar cells (OSCs) due to its excellent compatibility with various bulk heterojunction (BHJ) active layers. However, its intrinsically low electrical conductivity and suboptimal surface morphology limit hole extraction, ultimately constraining the performance of OSCs. To address this, we constructed an advanced heterojunction interface by introducing a wide-bandgap perovskite (CsPbBr) interlayer between the PEDOT:PSS and BHJ. The textured CsPbBr interlayer serves as an efficient hole transport modifier by enhancing extraction and transport efficiency, while simultaneously functioning as an energy donor via Förster resonance energy transfer (FRET) and as a photosensitizer capable of generating photocarriers independently through its intrinsic optoelectronic properties. This synergetic enhancement of charge generation, extraction, and transport properties resulted in an increase in the power conversion efficiency (PCE) of PM6:Y6-based OSCs from 16.80% to 17.74%, along with improved photocurrent and fill factor (FF). The universality of this approach was further demonstrated in state-of-the-art PM6:BTP-eC9:L8-BO systems, achieving a PCE of 19.02%. Our work elucidates the multifunctional role of CsPbBr in managing interfacial properties, presenting a feasible interface engineering strategy to achieve high-performance OSCs.
由于PEDOT:PSS与各种体异质结（BHJ）活性层具有出色的兼容性，它已在有机太阳能电池（OSC）中被广泛用作空穴传输层（HTL）。然而，其固有的低电导率和欠佳的表面形态限制了空穴提取，最终制约了OSC的性能。为了解决这一问题，我们通过在PEDOT:PSS和BHJ之间引入宽带隙钙钛矿（CsPbBr）中间层构建了一种先进的异质结界面。纹理化的CsPbBr中间层通过提高提取和传输效率充当高效的空穴传输改性剂，同时通过Förster共振能量转移（FRET）作为能量供体，并通过其固有光电特性独立产生光载流子的光敏剂。电荷产生、提取和传输特性的这种协同增强导致基于PM6:Y6的OSC的功率转换效率（PCE）从16.80%提高到17.74%，同时光电流和填充因子（FF）也得到改善。这种方法的通用性在最先进的PM6:BTP-eC9:L8-BO系统中得到进一步证明，实现了19.02%的PCE。我们的工作阐明了CsPbBr在管理界面特性方面的多功能作用，提出了一种实现高性能OSC的可行界面工程策略。
