Tetrahydroxy-Perylene Bisimide Embedded in a Zinc Oxide Thin Film as an Electron-Transporting Layer for High-Performance Non-Fullerene Organic Solar Cells.

Xinbo Wen,Zengqi Xie,Oliver Nagler,Agnieszka Nowak‐Król,Frank Würthner,Matthias Müller,Na Zhu,David Schmidt,Felix Kraus,Nan Zheng

doi:10.1002/anie.201907467

Abstract

By introduction of four hydroxy (HO) groups into the two perylene bisimide (PBI) bay areas, new HO‐PBI ligands were obtained which upon deprotonation can complex ZnII ions and photosensitize semiconductive zinc oxide thin films. Such coordination is beneficial for dispersing PBI photosensitizer molecules evenly into metal oxide films to fabricate organic–inorganic hybrid interlayers for organic solar cells. Supported by the photoconductive effect of the ZnO:HO‐PBI hybrid interlayers, improved electron collection and transportation is achieved in fullerene and non‐fullerene polymer solar cell devices, leading to remarkable power conversion efficiencies of up to 15.95 % for a non‐fullerene based organic solar cell.

Highlights

During the last decade a variety of new materials have emerged that are promising candidates for solar energy conversion into electricity on a technological scale.[1,2,3] In general, these photovoltaic devices rely on multiple layers which can either be inorganic or organic ones
Inspired by the widely applied 1,1’-bi-2-naphthol (BINOL)-ligands for transition-metal-catalyzed asymmetric catalysis[6] and an intriguing crystal structure published by Shibasaki and co-workers for a trinuclear ZnII-BINOL complex applied in catalytic asymmetric Mannich-type reactions,[7] we envisioned perylene bisimide (PBIs) dyes equipped with hydroxy functional groups in bay positions as coordinating ligands for Zn2+ ions for the incorporation of PBI dyes into zinc oxide (ZnO) semiconductor films[8] manufactured by the sol-gel process
It is remarkable that the performance of solar cells with HO-PBI-embedded ZnO thin films showed a significant increase in Jsc and fill factor (FF) simultaneously, and that these interlayers work well for both fullerene and non-fullerene solar cells

Summary

Organic Solar Cells Hot Paper

International Edition: DOI: 10.1002/anie.201907467 German Edition: DOI: 10.1002/ange.201907467 Xinbo Wen+, Agnieszka Nowak-Król+, Oliver Nagler, Felix Kraus, Na Zhu, Nan Zheng, Matthias Müller, David Schmidt, Zengqi Xie,* and Frank Würthner* Dedicated to Professor Michael R. Wasielewski on the occasion of his 70th birthday

Cathode interlayer

Findings

Conflict of interest