中文版 | English
CSpace
Relocating selenium alkyl chain enables efficient all-small molecule organic solar cells
Tian, Gengsui1,2,3; Li, Yulu1,2,3; Chen, Yao1; Duan, Tainan1; Hu, Dingqin1; Huang, Peihao1; Chen, Qianqian1; Liu, Heng4; Chen, Haiyan1; Lu, Xinhui4
2024-02-15
摘要Substituting sulfur with selenium in photoactive materials emerges as a promising strategy to enhance the performance of organic solar cells (OSCs). Typically, selenophene was incorporated into the conjugated backbone to replace thiophene. Conversely, the selenium-containing alkyl chain has garnered less attention in the context of OSCs. In this study, we fine-tune the active layer morphology by shifting the selenium-containing side chain from the para-position (T1) to the meta-position (T2). Notably, in conjunction with the nonfullerene acceptor BTP-eC9, the T2:BTP-eC9 blend demonstrates a significantly higher power conversion efficiency (PCE) compared to the T1:BTP-eC9 blend (14.30 % vs. 10.63 %). Analysis using Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM) reveals that the T2:BTP-eC9 blend exhibits a smoother surface and larger domain size, resulting in enhanced exciton dissociation efficiency (96.6 % for T2:BTP-eC9 vs. 90.9 % for T1:BTP-eC9). Grazing Incidence Wide Angle X-ray Scattering (GIWAXS) indicates that the T1:BTP-eC9 blend is less textured than the T2:BTP-eC9 blend, and space-charge limited current tests confirm lower and unbalanced hole/electron mobility in the T1:BTP-eC9 blend compared to T2:BTP-eC9. Charge recombination dynamics and donor-acceptor miscibility analysis further support these findings. The T2:BTP-eC9 OSCs demonstrate an impressive JSC of 26.73 mA/cm2, ranking among the reported to date for all small molecule OSCs.
关键词Organic Solar Cells Small Molecule Donors Miscibility Selenium
DOI10.1016/j.cej.2024.149149
发表期刊CHEMICAL ENGINEERING JOURNAL
ISSN1385-8947
卷号482页码:9
通讯作者Chen, Yao(chenyao@cigit.ac.cn) ; Duan, Tainan(tnduan@cigit.ac.cn) ; Hu, Dingqin(hudingqin@cigit.ac.cn) ; Lu, Shirong(lushirong@cigit.ac.cn) ; Xiao, Zeyun(xiao.z@cigit.ac.cn)
收录类别SCI
WOS记录号WOS:001171416800001
语种en