Enhancing Open-Circuit Voltage of High-Efficiency Nonfullerene Ternary Solar Cells with a Star-Shaped Acceptor

Guilong Cai; Yuhao Li; Jiadong Zhou; Peiyao Xue; Kuan Liu; Jiayu Wang; Zengqi Xie; Gang Li; Xiaowei Zhan; Xinhui Lu

doi:10.1021/acsami.0c14612

Enhancing Open-Circuit Voltage of High-Efficiency Nonfullerene Ternary Solar Cells with a Star-Shaped Acceptor

ACS Appl Mater Interfaces. 2020 Nov 11;12(45):50660-50667. doi: 10.1021/acsami.0c14612. Epub 2020 Oct 28.

Authors

Guilong Cai¹, Yuhao Li¹, Jiadong Zhou², Peiyao Xue³, Kuan Liu⁴, Jiayu Wang³, Zengqi Xie², Gang Li⁴, Xiaowei Zhan³, Xinhui Lu¹

Affiliations

¹ Department of Physics, The Chinese University of Hong Kong, New Territories 999077, Hong Kong, China.
² State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China.
³ Department of Materials Science and Engineering, College of Engineering, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Peking University, Beijing 100871, China.
⁴ The Department of Electronic and Information Engineering, Research Institute for Smart Energy (RISE), The Hong Kong Polytechnic University, Hung Hom, Kowloon 999077, Hong Kong, China.

PMID: 33112591
DOI: 10.1021/acsami.0c14612

Abstract

The ternary strategy has been widely used in high-efficiency organic solar cells (OSCs). Herein, we successfully incorporated a mid-band-gap star-shaped acceptor, FBTIC, as the third component into the PM6/Y6 binary blend film, which not only achieved a panchromatic absorption but also significantly improved the open-circuit voltage (V_OC) of the devices due to the high-lying lowest unoccupied molecular orbital (LUMO) of the FBTIC. Morphology characterizations show that star-shaped FBTIC molecules are amorphously distributed in the ternary system, and the finely tuned ternary film morphology facilitates the exciton dissociation and charge collection in ternary devices. As a result, the best PM6/Y6/FBTIC-based ternary OSCs achieved a power conversion efficiency (PCE) of 16.7% at a weight ratio of 1.0:1.0:0.2.

Keywords: fused-ring electron acceptor; nonfullerene acceptor; organic solar cell; star-shaped acceptor; ternary.