A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics

Kathryn M Wolfe; Shahidul Alam; Eva German; Fahad N Alduayji; Maryam Alqurashi; Frédéric Laquai; Gregory C Welch

doi:10.3762/bjoc.19.119

A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics

Beilstein J Org Chem. 2023 Oct 26:19:1620-1629. doi: 10.3762/bjoc.19.119. eCollection 2023.

Authors

Kathryn M Wolfe¹, Shahidul Alam², Eva German¹, Fahad N Alduayji², Maryam Alqurashi², Frédéric Laquai², Gregory C Welch¹

Affiliations

¹ Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta, T2N 1N4, Canada.
² King Abdullah University of Science and Technology (KAUST), KAUST Solar Center (KSC), Physical Sciences and Engineering Division (PSE), Material Science and Engineering Program (MSE), Thuwal 23955-6900, Saudi Arabia.

Abstract

Herein, we report on the design, synthesis, physical and chemical properties, and organic photovoltaic (OPV) device performance of four new cathode interlayer (CIL) materials based on bay N-annulated perylene diimides. Starting from the previously reported N-annulated perylene diimide (PDIN-H), the N-position was functionalized with a benzyl and pentafluorobenzyl group to make PDIN-B and PDIN-FB, respectively. Similarly, starting from the previously reported cyanated N-annulated perylene diimide (CN-PDIN-H), the N-position was functionalized with a benzyl and pentafluorobenzyl group to make CN-PDIN-B and CN-PDIN-FB, respectively. The materials exhibit solubility in the green solvent, ethyl acetate, and thus were processed into thin films using ethyl acetate as the solvent. The optoelectronic properties were assessed for both solution and film, and the electrochemical properties were probed in solution. To validate the potential as electron transporting layers, each film was used in conventional OPVs as the CIL with processing from ethyl acetate, while using a bulk heterojunction (BHJ) comprised of PM6:Y6. High power conversion efficiencies (PCEs) of 13% were achieved compared to control devices using the standard PFN-Br CIL.

Keywords: cathode interlayer materials; green solvent processing; organic photovoltaics.

Grants and funding

This work was supported by the NSERC Green Electronics Network (GreEN) (NETGP 508526-17), NSERC DG program (2019-04392), the NSERC I2I Program (I2IPJ 561742-2021), the Canada Foundation for Innovation, the Western Economic Development fund, and the University of Calgary. This work was partially supported by the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award No. OSR-2018-CARF/CCF-3079. SA and FL are very grateful for the financial support for conducting the research.