Abstract
Organic semiconducting materials with fluorine or chlorine substitution are commonly designed to prepare efficient polymer solar cells (PSCs) through finely modulating the energy levels and absorption spectra. Herein, two small molecular acceptors with fluorine substitution L8-BO or chlorine substitution eC9-2Cl are selected to prepare ternary PSCs with PM6 as polymer donor. The optimal ternary PSCs exhibit a power conversion efficiency of 18.66%, benefiting from the simultaneously increased open-circuit voltage (VOC) of 0.89 V, short-circuit current density (JSC) of 26.63 mA cm−2, and fill factor of 78.74% when the content of chlorine substitution eC9-2Cl is about 20 wt% in acceptors. Fluorinated and chlorinated substitutions can improve the VOC or JSC of the corresponding binary PSCs, which can be recombined into efficient ternary PSCs through optimizing their content in acceptors. Chlorinated materials have special crystalline conditions due to the specific features of the chlorine atoms with large atomic radius and the empty 3d orbits compared to the corresponding fluorinated materials. Adding an appropriate amount of the chlorine substitution eC9-2Cl further enhances the crystallization and intermolecular interaction of the ternary PSCs, which is beneficial for charge transport in the active layer and for device performance improvement.
Original language | English |
---|---|
Article number | 2200957 |
Journal | Solar RRL |
Volume | 7 |
Issue number | 1 |
DOIs | |
Publication status | Published - 2023 Jan |
Bibliographical note
Funding Information:This work was financially supported by the Fundamental Research Funds for the Central Universities (grant no. 2022JBZY012), the National Natural Science Foundation of China (grant nos. 62175011, 62105017, and 61975006), and the National Natural Science Foundation of China‐Swedish Foundation for International Cooperation in Research and Higher education (grant no. 62211530056).
Funding Information:
This work was financially supported by the Fundamental Research Funds for the Central Universities (grant no. 2022JBZY012), the National Natural Science Foundation of China (grant nos. 62175011, 62105017, and 61975006), and the National Natural Science Foundation of China-Swedish Foundation for International Cooperation in Research and Higher education (grant no. 62211530056).
Publisher Copyright:
© 2022 Wiley-VCH GmbH.
Keywords
- chlorinated acceptors
- fluorinated acceptors
- polymer solar cells
- power conversion efficiency
- ternary strategy
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering