Rational molecular and device design enables organic solar cells approaching 20% efficiency

Jiehao Fu; Qianguang Yang; Peihao Huang; Sein Chung; Kilwon Cho; Zhipeng Kan; Heng Liu; Xinhui Lu; Yongwen Lang; Hanjian Lai; Feng He; Patrick W K Fong; Shirong Lu; Yang Yang; Zeyun Xiao; Gang Li

doi:10.1038/s41467-024-46022-3

Rational molecular and device design enables organic solar cells approaching 20% efficiency

Nat Commun. 2024 Feb 28;15(1):1830. doi: 10.1038/s41467-024-46022-3.

Authors

Jiehao Fu^#¹, Qianguang Yang^#^{2

3

4}, Peihao Huang^{3

4}, Sein Chung⁵, Kilwon Cho⁵, Zhipeng Kan⁶, Heng Liu⁷, Xinhui Lu⁷, Yongwen Lang^{1

8}, Hanjian Lai⁸, Feng He⁸, Patrick W K Fong¹, Shirong Lu⁹, Yang Yang¹⁰, Zeyun Xiao^{11

12}, Gang Li¹³

Affiliations

¹ Department of Electrical and Electronic Engineering, Research Institute for Smart Energy (RISE), Photonic Research Institute (PRI), The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, 999077, PR China.
² School of Materials Science and Engineering, Taizhou University, Taizhou, 318000, PR China.
³ Thin-Film Solar Cell Technology Research Center, Chongqing Institute of Green and Intelligent Technology, Chongqing School, University of Chinese Academy of Sciences (UCAS Chongqing), Chinese Academy of Sciences, Chongqing, 400714, PR China.
⁴ University of Chinese Academy of Sciences, 100049, Beijing, PR China.
⁵ Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, 37673, South Korea.
⁶ School of Physical Science and Technology, Guangxi University, Nanning, 530004, PR China.
⁷ Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, 999077, PR China.
⁸ Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, PR China.
⁹ School of Materials Science and Engineering, Taizhou University, Taizhou, 318000, PR China. lushirong@cigit.ac.cn.
¹⁰ Department of Materials Science and Engineering, University of California Los Angeles (UCLA), Los Angeles, CA, 90095, USA.
¹¹ Thin-Film Solar Cell Technology Research Center, Chongqing Institute of Green and Intelligent Technology, Chongqing School, University of Chinese Academy of Sciences (UCAS Chongqing), Chinese Academy of Sciences, Chongqing, 400714, PR China. xiao.z@cigit.ac.cn.
¹² University of Chinese Academy of Sciences, 100049, Beijing, PR China. xiao.z@cigit.ac.cn.
¹³ Department of Electrical and Electronic Engineering, Research Institute for Smart Energy (RISE), Photonic Research Institute (PRI), The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, 999077, PR China. gang.w.li@polyu.edu.hk.

^# Contributed equally.

Abstract

For organic solar cells to be competitive, the light-absorbing molecules should simultaneously satisfy multiple key requirements, including weak-absorption charge transfer state, high dielectric constant, suitable surface energy, proper crystallinity, etc. However, the systematic design rule in molecules to achieve the abovementioned goals is rarely studied. In this work, guided by theoretical calculation, we present a rational design of non-fullerene acceptor o-BTP-eC9, with distinct photoelectric properties compared to benchmark BTP-eC9. o-BTP-eC9 based device has uplifted charge transfer state, therefore significantly reducing the energy loss by 41 meV and showing excellent power conversion efficiency of 18.7%. Moreover, the new guest acceptor o-BTP-eC9 has excellent miscibility, crystallinity, and energy level compatibility with BTP-eC9, which enables an efficiency of 19.9% (19.5% certified) in PM6:BTP-C9:o-BTP-eC9 based ternary system with enhanced operational stability.

Grants and funding

SRFS2223-5S01/Research Grants Council, University Grants Committee (RGC, UGC)