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 

机构地区：[1]Faculty of Electrical Engineering and Computer Science,Ningbo University,Ningbo 315211,China [2]Faculty of Material Science and Chemical Engineering,Ningbo University,Ningbo 315211,China [3]Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices,Ningbo Institute of Materials Technology&Engineering,Chinese Academy of Sciences,Ningbo 315201,China [4]Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences,Beijing 100049,China [5]Department of Chemical and Environmental Engineering,University of Nottingham Ningbo,Ningbo 315100,China

出　　处：《Science China Chemistry》2024年第3期963-972,共10页中国科学（化学英文版）

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)。

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.

关 键 词：alkylbenzene side-chain morphology regulation ternary blends organic solar cells 

分 类 号：TM914.4[电气工程—电力电子与电力传动]