Highly efficient ternary organic solar cells with excellent open-circuit voltage and fill factor via precisely tuning molecular stacking and morphology

作     者：Dinghong Sun Zhenyu Chen Jianfeng Zhang Wei Song Jingyu Shi Jintao Zhu Yuanyuan Meng Fei Jin Shuncheng Yang Ziyi Ge 

作者机构：Faculty of Electrical Engineering and Computer ScienceNingbo UniversityNingbo 315211China Faculty of Material Science and Chemical EngineeringNingbo UniversityNingbo 315211China Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and DevicesNingbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo 315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Department of Chemical and Environmental EngineeringUniversity of Nottingham NingboNingbo 315100China 

出 版 物：《Science China Chemistry》 (中国科学（化学英文版）)

年 卷 期：2024年第67卷第3期

页      面：963-972页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：supported by the National Science Fund for Distinguished Young Scholars(21925506) the National Key R&D Program of China(2017YFE0106000) the National Natural Science Foundation of China(U21A20331,51773212,81903743) Ningbo S&T Innovation 2025 Major Special Programme(2018B10055) CAS Key Project of Frontier Science Research(QYZDB-SSW-SYS030) Ningbo Natural Science Foundation(2021J192) 

主　　题：alkylbenzene side-chain morphology regulation ternary blends organic solar cells 

摘      要：The micro-morphology and molecular stacking play a key role in determining the charge transport process and nonradiative energy loss, thus impacting the performances of organic solar cells(OSCs). To address this issue, a non-fullerene acceptor PhC6-IC-F with alkylbenzene side-chain, possessing optimized molecular stacking, complementary absorption spectra and forming a cascade energy level alignment in the PM6:BTP-eC9 blend, is introduced as guest acceptor to improve efficiency of ternary OSCs. The bulky phenyl in the side-chain can regulate crystallinity and optimizing phase separation between receptors in ternary blend films, resulting in the optimal phase separations in the ternary films. As a result, high efficiencies of 18.33% as photovoltaic layer are obtained for PhC6-IC-F-based ternary devices with excellent fill factor(FF) of 78.92%. Impressively, the ternary system produces a significantly improved open circuit voltage(V_(oc)) of 0.857 V compared with the binary device,contributing to the reduced density of trap states and suppressed non-radiative recombination result in lower energy loss. This work demonstrates an effective approach for adjusting the aggregation, molecular packing and fine phase separation morphology to increase V_(oc) and FF, paving the way toward high-efficiency OSCs.