Asymmetric Non-Fullerene Acceptor Derivatives Incorporated Ternary Organic Solar Cells

Ai Lan; Jintao Zhu; Zhuohan Zhang; Yifan Lv; Hong Lu; Ningxin Zhao; Hainam Do; Zhi-Kuan Chen; Fei Chen

doi:10.1021/acsami.3c06981

Asymmetric Non-Fullerene Acceptor Derivatives Incorporated Ternary Organic Solar Cells

ACS Appl Mater Interfaces. 2023 Aug 23;15(33):39657-39668. doi: 10.1021/acsami.3c06981. Epub 2023 Aug 14.

Authors

Ai Lan^{1

2}, Jintao Zhu^{1

2}, Zhuohan Zhang^{1

2}, Yifan Lv^{1

2}, Hong Lu¹, Ningxin Zhao¹, Hainam Do^{1

2

3}, Zhi-Kuan Chen⁴, Fei Chen⁴

Affiliations

¹ Department of Chemical and Environmental Engineering, The University of Nottingham Ningbo China, Ningbo 315100, China.
² New Materials Institute, University of Nottingham Ningbo China, Ningbo 315100, China.
³ Key Laboratory of Carbonaceous Waste Processing and Process Intensification Research of Zhejiang Province, University of Nottingham Ningbo China, Ningbo 315100, China.
⁴ Key Laboratory of Flexible Electronics of Zhejiang Province, Ningbo Institute of Northwestern Polytechnical University, Ningbo 315100, China.

PMID: 37578345
DOI: 10.1021/acsami.3c06981

Abstract

Incorporating ITIC derivatives as guest acceptors into binary host systems is an effective strategy for constructing high-performance ternary organic solar cells (TOSCs). In this work, we introduced A-D-A type ITIC derivatives PTBTT-4F (asymmetric) and PTBTP-4F (symmetric) into the PM6:BTP-BO-4F (Y6-BO) binary blend and investigated the impacts of two guest acceptors on the performance of TOSCs. Differentiated device performance was observed, although PTBTT-4F and PTBTP-4F presented similar chemical structures and comparable absorptions. The PTBTT-4F ternary devices exhibited an improved power conversion efficiency (PCE) of 17.67% with increased open circuit (V_OC) and current density (J_SC), whereas the PTBTP-4F-based ternary devices yielded a relatively lower PCE of 16.34%. PTBTT-4F showed much better compatibility with the host acceptor BTP-BO-4F, so that they formed a well-mixed alloy phase state; more precise phase separation and increased crystallinity were thus induced in the ternary blends, leading to reduced molecular recombination and improved charge mobilities, which contributed to improved fill factors of the ternary devices. In addition, the optimized PTBTT-4F devices exhibited good performance tolerance of the photoactive layer thickness, as they even delivered a PCE of 15.25% when the active layer was as thick as up to ∼300 nm.

Keywords: asymmetric non-fullerene acceptors; energy loss; film morphology; organic solar cells; ternary strategy.