Acta Chimica Sinica ›› 2024, Vol. 82 ›› Issue (3): 257-264.DOI: 10.6023/A23100439 Previous Articles     Next Articles



邓燧楠, 刘海珍, 张连杰*(), 罗文君, 罗妹, 张泽升, 梁嘉豪, 王新康, 陈军武*()   

  1. 华南理工大学 高分子光电材料与器件研究所 发光材料与器件国家重点实验室 广州 510640
  • 投稿日期:2023-10-08 发布日期:2023-12-27
  • 基金资助:
    国家自然科学基金(22179040); 国家自然科学基金(51521002); 国家重点研发计划(2019YFA0705900); 广东省基础与应用基础研究重大项目(2019B030302007); 广东省自然科学基金(2022A1515011633)

Construction of Novel Polymers with Phenyl Substituted Benzodithiophenedione for Photovoltaic Performance Study

Suinan Deng, Haizhen Liu, Lianjie Zhang(), Wenjun Luo, Mei Luo, Zesheng Zhang, Jiahao Liang, Xinkang Wang, Junwu Chen()   

  1. Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China
  • Received:2023-10-08 Published:2023-12-27
  • Contact: *E-mail:;
  • Supported by:
    National Natural Science Foundation of China(22179040); National Natural Science Foundation of China(51521002); National Key Research and Development Program of China(2019YFA0705900); Basic and Applied Basic Research Major Program of Guangdong Province(2019B030302007); Natural Science Foundation of Guangdong Province(2022A1515011633)

Owing to the continuous development of materials and devices, the power conversion efficiency (PCE) of organic photovoltaics (OPV) has been improved continuously. However, there are some extra treatments used, which are not conducive to the large-scale production of OPV. Reasonably adjusting the solubility, crystallinity, and phase morphology of active layer could be of great importance to simplify processibility and directly obtain high-performance as-cast devices. In this work, a new phenyl substituted benzodithiophenedione unit (m-PhEh-BDD) was designed and synthesized through a facile selective acylation due to the aromatic difference between benzene and thiophene rings. When m-PhEh-BDD used as the third unit to modify the PM6, two new random polymers, namely FBDT-m10 and FBDT-m20 were obtained successfully. For direct comparison, the m-PhEh-BDD-based alternating polymer FBDT-m100 was also synthesized. With the mole content of m-PhEh-BDD moiety increasing, the highest occupied molecular orbital (HOMO) levels of the polymers gradually downshift but their bandgap values almost are identical. Moreover, FBDT-m100 shows less aggregation ability than PM6, suggesting that m-PhEh-BDD unit can modulate the aggregation behavior. Owing to the suitable aggregation and processibility, FBDT-m10 with moderate content of m-PhEh-BDD exhibits the best compatibility with non-fullerene acceptor Y6-BO, resulting in the superior blend morphology. Therefore, the as-cast devices based on FBDT-m10 can obtain the champion PCE of 16.06%, with a good fill factor of 71.14%. Additionally, the FBDT-m10-based device shows better storage stability than that based on PM6. After 7 d of storage, FBDT-m10-based device can maintain 87% of its initial PCE whereas the PM6-based device only kept 58% of its initial PCE. When the m-PhEh-BDD content increasing, the as-cast devices of the same storage time encounter a decrease in PCE, indicating suitable m-PhEh-BDD content is beneficial for long-term stability. This work demonstrates that the further exploitation on phenyl-substituted benzodithiophenedione unit could be a potential venue to achieve promising polymers for high-performing and stable organic solar cells.

Key words: aromatic substitution, benzodithiophenedione, polymer donor, organic photovoltaics