A Heteronuclear W/Cu/S Clusters‐Based Donor–Acceptor Polymer for Perovskite Solar Cells

• Published in: Advanced functional materials Vol. 34; no. 42
• Main Authors: Yao, Xiaoqiang, Fang, Zihan, Ren, Huarong, Mu, Xijiao, Xiao, Guo‐Bin, Zou, Xiaoxin, Cao, Jing
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.10.2024
• Subjects: Charge materials; Charge transport; Clusters; donor–acceptor polymers; Functional groups; heteronuclear; Hole mobility; Ligands; perovskite solar cells; Perovskites; Photovoltaic cells; Polymer films; Polymers; Solar cells; W/Cu/S Clusters
• DOI: 10.1002/adfm.202404671
• ISSN: 1616-301X

Designing the donor–acceptor polymers‐based modifiers with good charge mobility and abundant surface functional groups to bind on perovskite material is highly demanded to boost interfacial charge extraction and transport while yet realized. Here, two [WS4Cu4Br]+ and [WS4Cu5Br2]+ cluster units are bridged by triphenylamine ligands to yield an unprecedented a heteronuclear W/Cu/S clusters‐based donor–acceptor polymer. Due to the effect of Rydberg orbital components in different clusters mainly contributed by Cu ions, Cu‐rich units have negative potential, whereas Cu‐deficient groups display positive potential. This facilitates the formation of a circuit network with ligands acting as “wires” to realize efficient charge transport. Mobility tests reveal that the hole mobility of polymer film is 3.81 × 10−5 cm2 V−1 s−1. Such a polymer can efficiently extract and transport the holes from perovskite film, and thus improving the cell performance and stability. This work opens the opportunities for designing donor–acceptor polymers based on heteronuclear W/Cu/S clusters. A heteronuclear clusters‐based donor‐acceptor polymer is prepared by bridging two [WS4Cu4Br]+ and [WS4Cu5Br2]+ cluster units with triphenylamine ligands. In such a polymer, Cu‐deficient unit can be as donor unit and another is the acceptor, resulting in hole mobility of this polymer film up to 3.81 × 10−5 cm2 V−1 s−1. This polymer with highly exposed S and Cu surface sites from cluster centers can be efficiently bound on the surface of lead halide perovskite film, contributing to the improved efficiency and stability of perovskite solar cells.