Passivating Defects of Perovskite Solar Cells with Functional Donor‐Acceptor–Donor Type Hole Transporting Materials

• Published in: Advanced functional materials 2023-01, Vol.33 (1), p.n/a
• Main Authors: Daskeviciute‐Geguziene, Sarune, Zhang, Yi, Rakstys, Kasparas, Xiao, Chuanxiao, Xia, Jianxing, Qiu, Zhiheng, Daskeviciene, Maryte, Paskevicius, Tomas, Jankauskas, Vygintas, Asiri, Abdullah M., Getautis, Vytautas, Nazeeruddin, Mohammad Khaja
• Format: Article
• Language: English
• Subjects: Coupling (molecular); Cross coupling; Defects; defects passivation; donor‐acceptor‐donor; Energy conversion efficiency; fluorene; Malononitrile; Materials science; perovskite solar cells; Perovskites; Photovoltaic cells; Solar cells
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202208317

In this study, a series of donor–acceptor–donor (D‐A‐D) type small molecules based on the fluorene and diphenylethenyl enamine units, which are distinguished by different acceptors, as holetransporting materials (HTMs) for perovskite solar cells is presented. The incorporation of the malononitrile acceptor units is found to be beneficial for not only carrier transportation but also defects passivation via Pb–N interactions. The highest power conversion efficiency of over 22% is achieved on cells based on V1359, which is higher than that of spiro‐OMeTAD under identical conditions. This st shows that HTMs prepared via simplified synthetic routes are not only a low‐cost alternative to spiro‐OMeTAD but also outperform in efficiency and stability state‐of‐art materials obtained via expensive cross‐coupling methods. Engineering of donor–acceptor–donor functional enamine hole transporting materials is presented leading to the low‐cost hole transporting materia V1359 to reach power conversion efficiency over 22% in perovskite solar cells with excellent stability surpassing the reference spiro‐OMeTAD due to the incorporation of the malononitrile acceptor units that passivate the surficial perovskite defects via Pb–N interactions.