Engineering of dendritic dopant-free hole transport molecules:enabling ultrahigh fill factor in pero

• 作 者: Wei Chen Yang Wang Bin Liu Yajun Gao Ziang Wu Yongqiang Shi Yumin Tang Kun Yang Yujie Zhang Weipeng Sun Xiyuan Feng Frédéric Laquai Han Young Woo Aleksandra B.Djuri?i(c) Xugang Guo Zhubing He
• 机 构: Department of Materials Science and Engineering,Southern University of Science and Technology,Shenzh
• 出 处: 中国科学：化学（英文版）
• 发表日期: 2021年1期
• 关键词: dendritic molecules hole-transporting materials dopant-free ultrahigh fill facto

Developing dopant-free hole-transporting materials(HTMs)for high-performance perovskite solar cells(PVSCs)has been a very active research topic in recent years since HTMs play a critical role in optimizing interfacial charge carrier kinetics and in turn determining device performance.Here,a novel dendritic engineering strategy is first utilized to design HTMs with a D-A type molecular framework,and diphenylamine and/or carbazole is selected as the building block for constructing dendrons.All HTMs show good thermal stability and excellent film morphology,and the key optoelectronic properties could be fine-tuned by varying the dendron structure.Among them,MPA-Cz-BTI and MCz-Cz-BTI exhibit an improved interfacial contact with the perovskite active layer,and non-radiative recombination loss and charge transport loss can be effectively suppressed.Conse-quently,high power conversion efficiencies(PCEs)of 20.8％and 21.35％are achieved for MPA-Cz-BTI and MCz-Cz-BTI based devices,respectively,accompanied by excellent long-term storage stability.More encouragingly,ultrahigh fill factors of 85.2％and 83.5％are recorded for both devices,which are among the highest values reported to date.This work demonstrates the great potential of dendritic materials as a new type of dopant-free HTMs for high-performance PVSCs with excellent FF.