Acid-Assisted Noncovalent Interaction with Enhanced Electron Transportation on Active/Interfacial Layers for 16.43% Nonfullerene Organic Solar Cells

As the power conversion efficiency (PCE) of nonfullerene acceptor (NFA) organic solar cells (OSCs) rapidly developed, a new request is brought forward on OSCs' interfacial modification due to the NFA's conformational anisotropy. The interaction between the acceptors and an interfacial layer is particularly important for the interfacial materials. Herein, we demonstrated the noncovalent interactions between the NFAs and an electron transport layer (ETL) to form the effective electron transport channels. After introducing amino terminal substituted perylene diimide (PDIN) with the assistance of acetic acid (AA), the device yields a high PCE of 16.43%. The enhancement of similar to 51 and similar to 7% is observed for the pristine PDIN- and amino N-oxide terminal substituted perylene diimide (PDINO)-based OSCs. The enhanced PCEs were mainly attributed to the increase in electron transport from the newly established noncovalent interaction. Our results provide a feasible choice for the design of an efficient interfacial layer for high-performance nonfullerene photovoltaics.

Automated summary

With the rapid development of power conversion efficiency in nonfullerene acceptor organic solar cells, there is a new demand for interfacial modification due to the conformational anisotropy of NFAs. Noncovalent interactions between NFAs and an electron transport layer were found to enhance electron transport, leading to improved device performance.