New Insight into the Lewis Basic Sites in Metal–Organic Framework-Doped Hole Transport Materials for Efficient and Stable Perovskite Solar Cells

作者：Jiaqi Wang, Jian Zhang, Yulin Yang, Shuang Gai, Yayu Dong, Lele Qiu, Debin Xia, Xiao Fan, Wei Wang, Boyuan Hu, Wei Cao, Ruiqing Fan · 发表于：ACS Applied Materials & Interfaces · 年份：2021 · DOI：10.1021/acsami.0c19968 · 被引用次数：55 · 研究领域：Perovskite Materials and Applications、Conducting polymers and applications、Organic Light-Emitting Diodes Research

Currently, Spiro-OMeTAD is the most widely used hole transport material (HTM) in the best-performing perovskite solar cells (PSCs), resulting from its suitable energy level and facile processing. However, the intrinsic properties of organic molecules, such as low conductivity and a nonpolar contact interface, will limit the power conversion efficiency (PCE) and stability of Spiro-OMeTAD-based PSCs. Chemical doping could be an effective strategy to ameliorate the performance of Spiro-OMeTAD, and most of the dopants are designed for controllably oxidizing Spiro-OMeTAD. In this work, a highly stable metal–organic framework {[Zn(Hcbob)]·(solvent)} n (Zn-CBOB) with rod topology and Lewis basic sites is assembled and employed as a dopant for the hole transport layer. It is found that Zn-CBOB not only controllably oxidizes Spiro-OMeTAD and improves the conductivity of the HTM but also passivates the surface traps of the perovskite film by coordinating with Pb 2+ . The Zn-CBOB-doped PSCs achieved a remarkable PCE of 20.64%. In addition, the hydrophobicity of Zn-CBOB can prevent water from destroying the perovskite layer, which helps elevate the stability of PSCs.