Lawton Jack, Wagner Justine S, Xiao Xiangyu, Kim Sanggyun, Österholm Anna M, Shen D Eric, Sabury Sina, Perini Carlo A R, Datta Kunal, LaFollette Diana K, Li Ruipeng, Reynolds John R, Correa-Baena Juan-Pablo
School of Materials Science and Engineering, Georgia Institute of Technology, North Ave NW, Atlanta, Georgia 30332, United States.
Georgia Institute of Technology School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
Chem Mater. 2025 Aug 26;37(17):6655-6666. doi: 10.1021/acs.chemmater.5c01186. eCollection 2025 Sep 9.
Thermally evaporated organic electron transport layers (ETLs) have the potential to enable high-performance and scalable perovskite solar cells (PSCs). Among these, naphthalene diimide (NDI)-based ETLs are a promising family of materials that exhibit the optoelectronic properties, ambient stability and versatility required of high-performance ETLs. Here, we synthesized five NDI derivatives with varying functional groups and identified the two most promising candidates for evaluating the impact of molecular structure on processability via thermal evaporation. While phosphonic acid functionalization was shown to introduce thermal instability, leading to chemical changes during evaporation, NDI-bis -phenyl-bromide (NDI-(PhBr)) emerged as a promising ETL candidate. NDI-(PhBr) demonstrated excellent compatibility with the thermal evaporation process and enabled PSCs with power conversion efficiencies (PCEs) of 15.6%, surpassing all previously reported PSCs containing thermally evaporated NDI ETLs. Furthermore, NDI-(PhBr) exhibited excellent operational stability, retaining 75% of the initial PCE after 150 h of operation under continuous illumination at 65 °C. These results highlight the potential of NDI-based ETLs for advancing the scalability and performance of PSCs.
热蒸发有机电子传输层（ETL）有潜力实现高性能且可扩展的钙钛矿太阳能电池（PSC）。其中，基于萘二酰亚胺（NDI）的ETL是一类很有前景的材料，具有高性能ETL所需的光电特性、环境稳定性和多功能性。在此，我们合成了五种具有不同官能团的NDI衍生物，并确定了两种最有前景的候选物，以评估分子结构对热蒸发加工性能的影响。虽然膦酸官能化显示会引入热不稳定性，导致蒸发过程中发生化学变化，但NDI-双-苯基-溴化物（NDI-(PhBr)）成为了一种有前景的ETL候选物。NDI-(PhBr)表现出与热蒸发工艺的优异兼容性，并使PSC的功率转换效率（PCE）达到15.6%，超过了所有先前报道的含有热蒸发NDI ETL的PSC。此外，NDI-(PhBr)表现出优异的运行稳定性，在65°C连续光照下运行150小时后仍保留初始PCE的75%。这些结果突出了基于NDI的ETL在提升PSC的可扩展性和性能方面的潜力。
