Organic, nonfullerene semiconductors capable of self-assembly and composed of either anthraquinone (AQ) or naphthalenediimide (NDI) central fragments have been designed as electron-selective materials for n-i-p perovskite solar cells (PSCs). Both types of self-assembled monolayer (SAM) molecules contain phosphonic acid as an anchoring group, allowing covalent binding with indium tin oxide (ITO) surfaces. In particular, the NDI-based SAMs showed a more homogeneous anchoring on the ITO substrate and a stronger band bending at the ITO-SAM/perovskite interface than AQ-based SAMs. As a result, low-temperature-processed n-i-p PSCs with NDI SAMs as an electron-selective bottom contact showed a maximum power conversion efficiency (PCE) of 21.5%, representing the highest PCE among n-i-p PSCs with organic electron transporting layers (ETLs). In addition, our NDI-SAM-based devices demonstrate substantially improved long-term stability under operating temperature conditions when compared to devices using SnO₂ as the ETL.

中文翻译：

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非富勒烯自组装单分子层作为压区钙钛矿太阳能电池的电子选择性接触

能够自组装并由蒽醌（AQ）或萘二亚胺（NDI）中心片段组成的有机非富勒烯半导体已被设计为nip钙钛矿太阳能电池（PSC）的电子选择性材料。两种类型的自组装单层 (SAM) 分子都含有膦酸作为锚定基团，允许与氧化铟锡 (ITO) 表面共价结合。特别是，与基于 AQ 的 SAM 相比，基于 NDI 的 SAM 在 ITO 基板上表现出更均匀的锚定，并且在 ITO-SAM/钙钛矿界面处表现出更强的能带弯曲。结果，以NDI SAM作为电子选择性底部接触的低温处理的压区PSC的最大功率转换效率（PCE）为21.5%，是具有有机电子传输层（ETL）的压区PSC中最高的PCE。此外，与使用 SnO ₂作为 ETL 的器件相比，我们基于 NDI-SAM 的器件在工作温度条件下表现出显着改善的长期稳定性。