Expanding the low-dimensional interface engineering toolbox for efficient perovskite solar cells

• Main Authors: Ye, Senyun, Rao, Haixia, Feng, Minjun, Xi, Lifei, Yen, Zhihao, Seng, Debbie Hwee Leng, Xu, Qiang, Boothroyd, Chris, Chen, Bingbing, Guo, Yuanyuan, Wang, Bo, Salim, Teddy, Zhang, Qiannan, He, Huajun, Wang, Yue, Xiao, Xingchi, Lam, Yeng Ming, Sum, Tze Chien
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2023
• Subjects: Engineering::Materials::Photonics and optoelectronics materials; Engineering::Materials::Material testing and characterization; Halide Perovskites; Capping Layer; Solar Cells; High Efficiency
• Online Access: https://hdl.handle.net/10356/164911

Three-dimensional/low-dimensional perovskite solar cells afford improved efficiency and stability. The design of low-dimensional capping materials is constrained to tuning the A-site organic cation, as Pb2+ and Sn2+ are the only options for the metal cation. Here we unlock access to a library of low-dimensional capping materials with metal cations beyond Pb2+/Sn2+ by processing a full precursor solution containing both metal and ammonium halides. This enables easier synthetic control of the low-dimensional capping layer and greater versatility for low-dimensional interface engineering. We demonstrate that a zero-dimensional zinc-based halogenometallate (PEA2ZnX4; PEA = phenethylammonium, X = Cl/I) induces more robust surface passivation and stronger n–N isotype three-dimensional/low-dimensional heterojunctions than its lead-based counterpart. We exhibit p–i–n solar cells with 24.1% efficiency (certified 23.25%). Our cells maintain 94.5% initial efficiency after >1,000 h of operation at the maximum power point. Our findings expand the material library for low-dimensional interface engineering and stabilization of highly efficient three-dimensional/low-dimensional perovskite solar cells.