Unidirectional Sidechain Engineering to Construct Dual-Asymmetric Acceptors for 19.23 % Efficiency Organic Solar Cells with Low Energy Loss and Efficient Charge Transfer

Qunping Fan; Ruijie Ma; Jie Yang; Jingshun Gao; Hairui Bai; Wenyan Su; Zezhou Liang; Yue Wu; Lingxiao Tang; Yuxiang Li; Qiang Wu; Kun Wang; Lihe Yan; Rui Zhang; Feng Gao; Gang Li; Wei Ma

doi:10.1002/anie.202308307

Unidirectional Sidechain Engineering to Construct Dual-Asymmetric Acceptors for 19.23 % Efficiency Organic Solar Cells with Low Energy Loss and Efficient Charge Transfer

Angew Chem Int Ed Engl. 2023 Sep 4;62(36):e202308307. doi: 10.1002/anie.202308307. Epub 2023 Jul 28.

Authors

Qunping Fan¹, Ruijie Ma², Jie Yang³, Jingshun Gao^{1

4}, Hairui Bai¹, Wenyan Su⁵, Zezhou Liang⁶, Yue Wu⁷, Lingxiao Tang¹, Yuxiang Li⁵, Qiang Wu¹, Kun Wang⁴, Lihe Yan⁶, Rui Zhang⁸, Feng Gao⁸, Gang Li², Wei Ma¹

Affiliations

¹ State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China.
² Department of Electrical and Electronic Engineering, Research Institute for Smart Energy (RISE), Guangdong-Hong Kong-Macao (GHM) Joint Laboratory for Photonic-Thermal-Electrical Energy Materials and Devices, The Hong Kong Polytechnic University Hung Hom, Kowloon, Hong Kong, 999077, China.
³ School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, China.
⁴ School of Materials and Chemical Engineering, Zhongyuan University of Technology, Zhengzhou, 451191, China.
⁵ School of Materials Science and Engineering, Xi'an University of Science and Technology, Xi'an, 710054, China.
⁶ Key Laboratory for Physical Electronics and Devices of the Ministry of Education & Shaanxi, Key Lab of Photonic Technique for Information, School of Electronics Science & Engineering, Faculty of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, 710049, China.
⁷ Laboratory of Advanced Optoelectronic Materials, Suzhou Key Laboratory of Novel Semiconductor-Optoelectronics Materials and Devices, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China.
⁸ Department of Physics, Chemistry and Biology (IFM), Linköping University, 58183, Linköping, Sweden.

PMID: 37463122
DOI: 10.1002/anie.202308307

Abstract

Achieving both high open-circuit voltage (V_oc ) and short-circuit current density (J_sc ) to boost power-conversion efficiency (PCE) is a major challenge for organic solar cells (OSCs), wherein high energy loss (E_loss ) and inefficient charge transfer usually take place. Here, three new Y-series acceptors of mono-asymmetric asy-YC11 and dual-asymmetric bi-asy-YC9 and bi-asy-YC12 are developed. They share the same asymmetric D₁ AD₂ (D₁ =thieno[3,2-b]thiophene and D₂ =selenopheno[3,2-b]thiophene) fused-core but have different unidirectional sidechain on D₁ side, allowing fine-tuned molecular properties, such as intermolecular interaction, packing pattern, and crystallinity. Among the binary blends, the PM6 : bi-asy-YC12 one has better morphology with appropriate phase separation and higher order packing than the PM6 : asy-YC9 and PM6 : bi-asy-YC11 ones. Therefore, the PM6 : bi-asy-YC12-based OSCs offer a higher PCE of 17.16 % with both high V_oc and J_sc , due to the reduced E_loss and efficient charge transfer properties. Inspired by the high V_oc and strong NIR-absorption, bi-asy-YC12 is introduced into efficient binary PM6 : L8-BO to construct ternary OSCs. Thanks to the broadened absorption, optimized morphology, and furtherly minimized E_loss , the PM6 : L8-BO : bi-asy-YC12-based OSCs achieve a champion PCE of 19.23 %, which is one of the highest efficiencies among these annealing-free devices. Our developed unidirectional sidechain engineering for constructing bi-asymmetric Y-series acceptors provides an approach to boost PCE of OSCs.

Keywords: Charge Transfer; Dual-Asymmetric Acceptors; Energy Loss; Organic Solar Cells; Sidechain Engineering.

Abstract

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